Although they get on, brother and sister Jo and Edward Berry have taken very different paths since the day that their lives changed irrevocably.
When their father, Tory MP Sir Anthony Berry, was killed in the IRA bomb attack on Brighton's Grand Hotel 40 years ago today, Jo vowed to draw something 'positive' out of the experience.
That lead her to not only meet her father's killer, but form what she described to MailOnline this week as an 'unusual friendship' with him.
Jo, now 67, has since shared a platform with former terrorist Patrick Magee more than 300 times as part of her decades-long campaign for peace and conflict resolution.
She did that because she firmly believes that Magee - who was given eight life sentences in 1986 before being freed in 1999 under the terms of Good Friday Agreement- has changed.
And in a BBCdocumentary that aired on Wednesday, Magee said the experience of meeting Jo for the first time and realising that her father was a loving, decent man rather than a 'cypher' was 'shattering'. He said he told her: 'I'm sorry I killed your dad.'
He has, however, never recanted his past actions and continues to refuse to give anything but minor details about how exactly he planted the bomb that killed five people.
But Edward, 64, who like his sister also featured in this week's documentary, is not interested Magee's personal journey. He told MailOnline separately to his sibling that he has 'no engagement with this man at all'.
The former terrorist was a 'functionary' who was 'told to do a job', he said.
Jo Berry and Patrick Magee at the Old Market in Brighton on the 30th anniversary of the bombing of the Grand Hotel in Brighton in 2014. Magee planted the bomb. Jo's father, Sir Anthony Berry, was among the five people who were killed
Jo and Edward Berry with their siblings Antonia and Alexandra and their father, Conservative MP Anthony Berry
Jo's brother Edward, 64, has taken a very different path in life to his sister. He has never met Patrick Magee and has no desire to
And asked if he had strong feelings when Jo first met Magee, he said he has 'no comment', but did insist: 'If her work has done good, then then who am I to criticize that?'
Through their mother, Jo and Edward are first cousins of the latePrincess Diana, who they were both close to.
Although Edward was present when she married Prince Charles in St Paul's Cathedral in 1981, Jo, who had been living in India for more than two years, chose not to come home.
Diana was a guest when Edward's married one of her former school contemporaries in 1989. Her sons Prince William and Prince Harry were page boys.
Edward, who is now divorced, has not shared in his sister's passionate campaigning.
Instead, the father-of-three has had a long and successful career in the food and drink industry and is now a consultant.
Back in October 1984, Edward happened to be living in Brighton for work, and was fortunate to see his father the night before he died.
Jo, who also has three children, was staying with her sister in London and was set to go to Africa when tragedy struck.
Anthony, a former deputy chief whip in Margaret Thatcher's government, was in the seaside city along with hundreds of other MPs, ministers, aides and the PM herself for the Conservative Party conference.
Like Mrs Thatcher and most of the other attendees, he was staying at the Grand Hotel. Also with him was his second wife Sarah and their two Jack Russell Terriers.
On October 12, 1984, a bomb planted by IRA terrorist Patrick Magee in the Grand Hotel in Brighton exploded. The aim was to kill Margaret Thatcher following her refusal to back down in the face of hunger strikes
How the bomb planted by Patrick Magee devastated the Grand Hotel in Brighton on October 12, 1984
More than three weeks earlier, Magee had checked into the hotel under a false name - and hid the bomb in the bathroom of his room, number 629.
The device, which Magee - an experienced bomb maker - had built himself, was fitted with a long-delay timer.
When it exploded at 2.54am, the blast engulfed one of the two 11ft chimney stacks that stood atop the historic hotel.
The stack then careered through the hole created by the blast, ripping through several rooms.
Sir Anthony was among five people who were killed. His wife was among 31 others who were seriously injured.
Mrs Thatcher, who had been working on her party conference speech shortly before the bomb went off, narrowly escaped harm along with her husband Denis and Personal Private Secretary Robin Butler.
Her bathroom, which she had been in just minutes earlier, was severely damaged.
Edward said: 'I had a very nice dinner with my father and stepmother Sarah on the night of the 11th.
'He had a drink drive problem that had been reported in the press.
Sir Anthony Berry and his first wife Mary with their children, Jo (left), Antonia, Edward (on his mother's lap, and Alexandra
Jo (third from left) and Edward (left) with their siblings, father and stepmother Sarah in 1968. They were on their way to a memorial service for Sir Anthony's father, Viscount Kemsley, the former owner of the Sunday Times
Sir Anthony Berry married his second wife Sarah in 1966 and had two more children with her. Above: The couple on their wedding day
Patrick Magee (second from left) walking free from HM Prison Maze in Northern Ireland in 1999. He was released under the terms of the Good Friday Agreement
Jo Berry with Patrick Magee ahead of giving a talk together in 2004
Jo Berry sits next to Patrick Magee at a talk in Parliament on October 13, 2009
Patrick Magee (left) seen in a photo that was covertly taken by members of the Metropolitan Police's Special Branch
In June 1985, what had turned into an international manhunt for Patrick Magee came to an end. He was arrested and handed eight life sentences after a trial
In Tuesday's BBC documentary Bombing Brighton: The Plot to Kill Thatcher, Magee, now 73, said of his first meeting with Jo: 'In my head, something clicked. I killed this guy, who at some level, at many levels, created this woman'
'He took a dive. He was a man of high honour. He knew he had made a big mistake.
'[But] when I saw him in October he was absolutely back on top. We had a very warm dinner.
'If he had died a month or two earlier it would have been much sadder, just from his perspective.
'I said goodbye to him at 10.30 or 11. He went into the distance.
'I went to my flat, which was only two blocks away. Early the next morning I got a phone call from Jo saying, 'Is dad all right?'
'I asked her what she meant. She said there had been a bomb at the hotel.'
That is when the chaos began. Edward went to the Metropole Hotel, next-door to the Grand, and saw people 'covered in dust' inside.
He set about 'looking, looking, looking' for his father but could not see him.
Instead, he found out from police where his stepmother was being cared for, at the Royal Sussex County Hospital nearby, and went to see her.
Initially, he stopped off at the room of trade and industry secretary Norman Tebbit, who along with his wife had been seriously injured in the blast.
Edward said: 'He was awake but obviously very badly injured. He very kindly said: 'You better take some flowers for Sarah, because I've got rather a lot more than I need.'
Another moment that he remembers distinctly is reuniting his stepmother's beloved dogs.
The pets, who were mother and daughter, had survived the blast but were in two different places.
One was in the care of the RSPCA and the other was with the fire brigade.
'Putting the mother and daughter together was a moment of extraordinary emotion,' Edward said.
'It was the first moment I cried.'
There was not much time for tears in the hours and days that followed.
The first real worrying sign came when Jo anxiously watched the Tory conference on TV in the hope of seeing her father - but he wasn't there.
As millions saw the stoic Mrs Thatcher tell the shaken audience that 'all attempts to destroy democracy by terrorism will fail', Jo's mind was understandably on her father.
Then the worst news came. Edward was told that rescue workers had found what they believed to be Sir Anthony's body.
'I was asked whether I could identify the body, and I really couldn't, you know, I'm 24 years old, and that was not something I felt I could do,' he said.
'So I used a signet ring that I wear which was a present from my father and which matches one that he wore.'
'And then it was all rather quiet. That was the moment where the whole world just exploded,' Jo said.
One of her first reactions was to go out, dumbstruck, into the street and hit her thighs repeatedly as she said, 'Dad's dead, dead's dad, dad's dead', again and again.
It was part of her effort to force herself to accept what had happened.
Edward meanwhile went back to the hospital to see his stepmother.
After he had gone to buy a bottle of wine from a local off-licence, he and Sarah 'just talked.'
'It was a very gentle conversation,' he said. 'She knew earlier than I did. I think she was pretty clear that he probably had been killed, because he wasn't around.'
Edward is still close to his stepmother, who is now in her 80s.
Mrs Thatcher's suite escaped largely unscathed, besides the bathroom, which was severely damaged. Had she been in there getting ready for bed, she could have been killed
Margaret Thatcher seen alongside her husband Denis and personal assistant Cynthia Crawford as she leaves Brighton's Grand Hotel shortly after an IRA bomb attack, October 12, 1984
The scene outside the Grand Hotel in Brighton, after a bomb attack by the IRA
Injured guests leave the Grand Hotel in Brighton, after a bomb attack by the IRA
A policeman stands over a man who has been injured in the bomb blast at the Grand Hotel
A policeman in protective clothing searches for clues at the ruined Grand Hotel
The severe damage to a large section of the Grand Hotel, caused by a bomb blast which toppled a chimney stack
Just hours after the attack, Mrs Thatcher appeared at the Tory party conference. She told the party faithful: '...The fact that we are gathered here now, shocked but composed and determined, is a sign not only that this attack has failed, but that all attempts to destroy democracy by terrorism will fail'
'We speak often. And you know, without that conversation, I would have lost probably a big chunk of my relationship with my father, because we do talk about him every single time.
'It's what we would do, we'll always make a reference to him and keep his memory alive and enjoy those conversations,' he said.
In the days that followed, there was not time to grieve. Instead, he and Jo had to set about organising their father's funeral, and everything else that has to be sorted when a close relative dies.
There was one small blessing.
'The outpouring of love and affection and and just extraordinary positive words about my father and his life and his work was wonderful. It was repeated in hundreds of letters we received,' Edward said.
At a memorial service at St Margaret's Westminster, the de-facto church of the House of Commons, Mrs Thatcher read a lesson.
And then when Sir Anthony had been laid to rest, what came next?
'I just carried on,' Edward said. 'I had very good employers who allowed me to take as long as I wanted [away from work].
'I didn't find any sort of mission from it [losing his father]. I view it as just wrong place, wrong time.
'If you look back at the history of the IRA or any other terrorist organization, collateral is just one of those things.
'You're better off stepping back and enjoying what you did have, rather than sort of blaming everybody,' he said.
Meanwhile, Jo, who for years had had an avid interest in meditation and had 'already studied Gandhi and non-violence' when her father was killed, felt the need to go on a very different journey.
'The trauma was so huge that the only way to respond was to turn it around and bring some meaning and something positive out of it,' she said.
Jo went to Belfast for the first time in 1985 and gave her first talk not long afterwards.
Her organisation, Building Bridges for Peace, officially became a charity in 2009.
She met Magee the year after he was released. Why?
'I didn't want to have an enemy,' she said.
'I wanted to understand why someone would join the IRA, why someone would plant a bomb, and I wanted to understand what is it that can drive us to a point of using violence?
'I didn't want to have an enemy. I wanted to understand why someone would join the IRA, why someone would plant a bomb, and I wanted to understand what is it?
'What is in us that can drive us to a point of using violence?'
Her plan was to only meet Magee once.
'That was my intention, was never to see him again,' she said.
'But he said that he was disarmed by my empathy, which meant that his walls came down.
'He began to see my dad, rather than just a target, as a human being with a soul. He started on his journey, so that enabled me to then carry on meeting him'.
There is a caveat, though.
'It can be challenging being with him, like I don't forget why we met, what he did. He planted that bomb that killed my dad. That's never going to go away,' Jo added.
'It's an unusual friendship. It's a limiting word to describe it. It's not like a normal friendship. There's always some reason for us talking.
'Friends isn't the right word. But we are friends because I do care about him.'
In Tuesday's BBC documentary Bombing Brighton: The Plot to Kill Thatcher, Magee, now 73, said of his first meeting with Jo: 'In my head, something clicked. I killed this guy, who at some level, at many levels, created this woman.
The Daily Mail's coverage the day after the blast, detailing how Margaret Thatcher had been in her bathroom just minutes before it was wrecked by the blast
The Daily Mail's coverage of the 1984 bomb attack on the Grand Hotel in Brighton
The Daily Mail's coverage. It reported how Marks & Spencer opened early in Brighton so conference attendees could buy new clothes
A Daily Mail report on Princess Diana's attendance at Sir Anthony Berry's funeral with her sister Jane. The siblings were his nieces by marriage
'And that is shattering.That realisation, at some level, I had reduced him and what he stands for to the point where he is this cypher who you can take this action against.
'I had been reduced. Something in me had been narrowed.'
Since going 'public' in 2001, Magee and Jo have travelled to countries including Israel, Rwanda, and Kosovo to give shared talks on peace and conflict resolution.
Their next one is in London on October 16, followed by Belfast six days later.
The London one is at the same church where, just two days after her father was killed, Jo made her vow to herself to draw something positive from what had happened.
Others do not share her view of what she has chosen to do.
Lord Tebbit, 93, remains vociferously unforgiving towards Magee. His wife, who died in 2020, was left permanently disabled by the blast.
The former minister previously said: 'I am often asked if I can find it in my heart to forgive the creature, Patrick Magee. That is not possible, for Magee has never repented.
'One can hope that there's a particularly hot corner of Hell reserved for him and he can repent in his own time there.'
Jo conceded: 'I know it's very challenging for some people what I've done, and that's, that's fine.
'So as long as people are respectful I will engage in dialogue with anyone who feels differently to me.'
Would her father understand why she now spends time with Magee?
'We're never going to know, but I like to think that he would understand.
'It's because of how much I loved him, it's because of the pain that I went through that I've done this work,' she said.
Edward clearly does not share his sister's view of Magee. But, like her, has not spent the years since his father's death being angry and bitter.
He said: 'I don't like the idea that Magee was released, but I didn't wail and gnash my teeth and shout at the screen.I [just] have no engagement with this man at all.'
Edward was keen to stress though that he sees terrorism as cowardly.
'I think anyone who plants bombs is cowardly. If you've got anything, if you've got something you want to talk about, come out and discuss it.'
He added: 'I don't think it's the way to resolve anything.
'Because, in many ways, if you fight in that way, then the people who are fighting actually become even more resolute.'
What about Magee? How much has he changed? Jo said: 'At the moment, he doesn't think there's anything else they [the IRA] could have done.
'That is the difference between us, because I'm much more like, violence never works.'