The family of John Hogan's former wife said today they will fight to protect his daughter Mia from "unwanted intrusion by her father".
John Hogan will return to Britain within the next week after he was freed from a Greek psychiatric unit by a court in Athens on Friday.
While Hogan prepares to return to Bristol in the coming days his former wife Natasha Visser fears he will try to make contact with their young daughter Mia.
The 36-year-old killed six-year-old son Liam after jumping from a Crete hotel balcony with him and two-year-old Mia in his arms following an argument with Ms Visser.
Liam died of head injuries but Hogan and Mia survived with broken limbs following the plunge on August 15, 2006.
Hogan has been receiving treatment in a psychiatric hospital in Athens since he was cleared last year of murder.
He has reportedly spoken of his desire to be reunited with Mia, who lives with her mum in Australia, and has kept a diary to give to her when she is older to explain the tragic events.
Today Brian Chandler, the stepfather of Ms Visser and family spokesman, issued a statement on behalf of the family.
They say they have "great apprehension, but not surprise" at Hogan's wish to contact Mia.
"This is precisely what we have been afraid of, and he clearly has no idea how much damage and distress he has already caused to so many people's lives throughout two families," the statement said.
"I admire the Hogan family's steadfast resolve to help John, and in this, they have now succeeded.
"But in this process, the Hogan family have completely lost sight of Mia and Liam's rights.
"Liam did not deserve to die at age six and neither did Mia deserve the ongoing traumatic nightmares and the deep sense of loss for her loving brother that she has endured.
"Just imagine the psychological damage the experience alone has already done to a sensitive young girl.
"We want Mia to forget, for now, the terrifying events in August 2006, to have peaceful sleep, to have the happy childhood she deserves, and to live a normal life."
He added that Mia is "a very brave little girl" who is happy in her new life in Australia.
"Liam's rights are never forgotten by Natasha or her family, and Mia will be protected from unwanted intrusion by her father for as long as we think necessary," the statement continued.
"No mother would allow contact between a killer and his intended victim.
"Why should Natasha have to live with the constant fear that Hogan will suddenly contact Mia? Why should she live as a fugitive in the future, to ensure Mia's safety? The Hogan family will have to get to grips with the fact that Hogan, by his actions has shown that he is both dangerous, and unpredictable.
"By his attitude he has also shown that he should never be allowed contact with Mia. He forfeited that right in August 2006."
Hogan was found not guilty of murder on psychiatric grounds in January last year after a court on Crete upheld his defence that he had suffered an "earthquake of psychosis".
Hogan's mother and sister had both campaigned to Greek authorities to let him seek treatment in the UK where they said he would be given all the love and support he needs.
Earlier this month, the High Court quashed a 2006 inquest ruling that Hogan unlawfully killed his son, claiming the original verdict was flawed.
The Crown Prosecution Service has said no action would be taken against him in Britain.
Hogan, who still uses a crutch after the balcony leap, maintains he has no recollection of Liam's death.