Among the messages of sympathy and Mass cards which young Conor Leonard will continue to receive in the coming weeks, there will be a letter from someone who understands, perhaps more than anyone, exactly what he is going through.
Like Conor, who fought in vain to save his mother Concepta's life when she was attacked by her former partner at her home in Co Fermanagh last week, Jayne Stewart lost her mother, along with her father, in similarly tragic circumstances in 1991.
Then 16, Jayne came home one afternoon with her brother to find both parents dead at their house in Bangor. Her father Jack Sinclair (58), an RUC officer, had shot his wife Lorna (54) before turning the gun on himself.
Jayne was youngest of the four children born to the couple, who had met and worked together in the police, before Lorna left the force to raise her family.
Last week's murder-suicide in Maguiresbridge, which left Conor (30) with stab wounds, brought back horrific memories for Jayne (43), a mother-of-three. But the classroom assistant wants to reach out to Conor, who has Down's syndrome, to offer him hope in these darkest of days for him.
"The grief, the shock and the horror for Conor - I know that's overwhelming," says Jayne. "To think of it, it takes your breath away. He was so brave and so inspiring at the funeral.
"It was incredible to watch him carrying his mother's coffin. You could see his pain and his courage. It is so sad, so shocking. I trust that God will carry him through."
Jayne's father, like Concepta Leonard's killer Paedar Phair, was a violent, controlling man. He had subjected his wife and family to years of domestic abuse, and sexually abused Jayne from the age of 13. After years of trying to persuade her mother to leave, Lorna had finally agreed and had arranged for a divorce summons to arrive after her departure with the children.
Tragically, her husband received the summons, and murdered Lorna before she could make the getaway. "We'd planned to leave on the Wednesday," Jayne recalls. "I came home on the Monday with my brother - initially we thought it was a terrorist attack, as dad was in the RUC, and I thought the terrorists might still be in the house. It turned out Dad had shot himself only moments before we arrived. Mum was behind the door; we had to wedge it open. Dad was lying in full view, in front of the door, so we saw him first. I just ran out of the house in shock.
"He'd killed Mum in a fit of rage after the police had come to the house on the Monday - two days early - and served him with a divorce summons. He went and collected Mum from work and brought her home to murder her."
For years afterwards Jayne replayed the scene of carnage in her head and tried to numb the pain with drugs.
On top of her shock and grief, she also had to cope with the aftermath of three years of sexual abuse by her father.
"I gave as good as I got back at him verbally, so sexual abuse was his only way to control me," she remembers. "I lived with so many secrets; this was just another and I coped with it on my own, just as I did after Mum died.
"I didn't confide in Mum because of fear of what would happen if I did. What would happen in terms of how my dad would react if my mum confronted him, and also because I didn't trust the police.
"My mum had asked them to take his guns off him as he was abusive, but they said he was an exemplary officer and saw no case against him. So, I knew it was my word against his."
Jayne lived in constant fear of being raped by her father.
Along with reaching out to Conor Leonard through this article and her letter, she wants to give her advice to any young girl reading this interview who is also experiencing abuse.
"When I was 15, Dad gave me £5 and told me he would give me £5 every month and that I needed to go on the pill. His intentions were clear.
"For three years I had to be sure I was never left in the house alone with him, which was exhausting. I always had to know who was going out and where, and when they'd be back, and make plans around that.
"For years I felt the shame and guilt that, here I was - a pretty feisty girl, a girl who was not afraid to argue back with him despite the risk - allowing herself to be immobilised through fear and confusion.
"My advice to any girl experiencing sexual abuse or abuse of any kind is to tell an adult, because it is not their fault. It is not their guilt and not their shame and they don't have to carry that and they don't have to live in fear of anyone."
In the years following her parents' deaths Jayne's sister, who is nine years older, looked after the family.
As Jayne recalls: "It wasn't an easy task for her. I had gone off the rails a bit at 14 because of the domestic and sexual abuse, and I got worse after that. I took ecstasy, speed, acid, marijuana - I dabbled in whatever was there. I was just trying to numb the hurt.
"My sister and my older brother had faith and that really helped them through and gave them strength. My younger brother - he's married now with a great job and a nice home. He was able to put his life back together.
"It took me a bit longer. I was lost. I had no desire to heal, at that point, yet all I wanted was a family and some stability. I was angry at God but I still prayed. I asked him why he didn't answer my mother's prayers.
"But you can't blame God for what humankind does. It's a fallen world; there is so much hatred in it. That is not God's will. We have free will; it's us who cause the trouble. You can't point the finger at God."
Jayne doesn't believe that her father - as with any of us - was born evil. She attributes his viciousness to nurture rather than nature.
"I think his experience of life created his psychological problems. His mother died and his stepmother had been very abusive to him, physically," she says.
"I would also say that the pressures of being in the RUC, and what he saw and experienced, contributed to the evil that overtook him. But, despite that, we all choose our own behaviour. He should have got counselling.
"People are responsible for their own mental health; he could have got help. There was a reason for his behaviour but there are no excuses. I think his behaviour gave the devil a foothold. He became more violent and abusive. Domestic abuse progresses and builds up.
"My siblings have memories of better days but I don't remember him any other way. Abuse was the norm, but it wasn't normal, and it wasn't until I was older that I could acknowledge it as abuse."
At one stage in her late teens Jayne considered suicide. "It was a build-up of the years of abuse and the trauma of finding my parents dead. I was having horrific nightmares and I began to wonder if there was anything worth getting up for the next day.
"Then, I thought about Mum and remembered her teaching me about Jesus. I began to pray again and I was given hope. I prayed for a family and a safe home, and some stability and security. And I do believe God sent me Gerry."
Jayne met Gerry Stewart while at work in Bangor. They were friendly for five years before Gerry asked her out.
Jayne says: "He's like a saint. He taught me to love and to be loved. I didn't know how to. I'd been in relationships where I'd been treated abysmally because I thought it was all I deserved. Over time Gerry taught me what a real, loving relationship is.
"He wasn't a Christian then but we both got saved three-and-a-half years ago. He's a brilliant dad and he runs the BB at church."
The couple have three children, Charlie (13), Hayden (10) and Luke (8). Before she made a testimony at her local Elim Church in Bangor, telling the story of her tragic past, Jayne told her children about the domestic abuse, but only told her daughter of the sexual abuse. And she went on to give them a powerful lesson in forgiveness, by placing flowers on her father's grave. "Mum and dad are buried together - I don't know why. It wasn't my choice," she admits. "In my head, I had to separate them.
"To me it was Mum's grave, not Dad's.
"But I have forgiven him. I feel sorry for him.
"He missed out on so much and he caused so much pain and suffering and death.
"It's awful. I go to the grave mostly for Mum."
Lorna Sinclair was a religious person, whose faith kept her going throughout the years of domestic abuse, even when she and the children would be forced to go hungry.
"Dad was so manipulative and controlling in every way, including financially," says Jayne. "He didn't let her have any friends and he'd accuse her of having affairs, which was nonsense. There was always trouble.
"It's easy for people to say: 'Why didn't she just leave?'. But he took away all her confidence, her self-esteem and independence. Psychological abuse has a massive impact as well. He kept her dependent on him.
"On the outside he made it look like all was well but nobody knew how Mum had to fight for money to feed us. It was a constant battle. She didn't know how she could have provided for us if she'd left; she always put us first."
Now that Jayne has come to share the strong faith held by her mother, she is happy in the belief that she will see her again. She doesn't believe her father is in Heaven however, unless he repented in his last minutes.
"I think that's unlikely, and I believe that repentance has to happen on Earth," she asserts. "I can't wait to see Mum again. They say there are no tears in Heaven but there's bound to be tears of joy when I see her again.
"I remember how she smelt, of Olay, but I don't remember her voice."
As she sits down to write to Conor this weekend, Jayne hopes that her letter will lead to them meeting one day, if and when Conor is ready.
She adds: "I'd always be open to meeting Conor. I would tell him to take time with his grief and not to feel pressure to get over it too soon. I didn't share my grief or pain. You try to put a brave face on it and fit in with the rest of the world, but you have to allow others to support you.
"Grief has its own shelf life. People will say: 'Oh, he'll never get over this'. But God has created us with the capacity to cope and to heal. There is so much help out there; that sort of talk is self-defeating.
"I'd be mortally offended if people had said that to me. I am free from pain now and I do have a life. In the same way, it bothers me when victims of abuse are described as 'scarred for life'. I'm not.
"And Conor will heal with the help of the people around him who care for him, and he will go on to love life again. With God's help, he will be happy again, as I am."