Police were conducting more tests today to find out what happened to a man found dead with his young son.
Chris Hall, thought to have been in his 50s, was discovered with six-year-old son Chris at their home in Poole, Dorset, on Wednesday.
A family friend said Mr Hall had been going through an acrimonious split with his partner and feared losing custody of the child.
Post-mortem tests on the pair - known as Big Chris and Little Chris - failed to establish how they died yesterday.
A Dorset Police spokesman said: "Further inquiries and analysis are being undertaken to help establish cause of death."
No-one else was being sought in connection with the discovery in Queen's Road, the force said.
Neighbour and friend Phil Haley, 38, said Mr Hall had been incredibly upset by the split with partner Rachel Edwards.
He added that Mr Hall had also been experiencing "legal problems" with the cafe he ran with Ms Edwards at Nuffield Industrial Estate in Poole.
"He doted on his little boy, he meant everything to him. He was a lovely little boy, it's absolutely tragic, I don't know how they are going to explain it to the other kids at the school," Mr Haley said.
He said that Ms Edwards left Mr Hall in March or April this year, and that Mr Hall was distraught at the prospect of losing his son.
"It was a very difficult split-up, a lot of issues surrounding it that made it very difficult for Big and Little Chris at home.
"She did end up with someone else, that was the trigger that upset Big Chris. He wasn't selfish enough to know that that was the only reason for the split-up."
Mr Haley, a sales representative for a drinks company, added: "He was a very good man. Before people think he was evil, that was the last thing he was. He had a lot of morals, a lot of people liked him.
"He must have felt that to get himself and Little Chris out of the situation he was in, that was what he felt he had to do. I'm not saying that was the right thing but that must be how he felt."
Another neighbour, who didn't want to be named, said: "It's a real shock. They seemed like a nice family but you never know what goes on behind closed doors."
Another neighbour added: "People who do things like that should be brought back to life and killed again."