Animal loving ex-policewoman June Fairbrother from Harpenden planned to leave her £350,000 home to animal charities.
But after her 58-year-old nephew Kenneth King moved in to care for her, she changed her mind and left the house to him in the hope he would care for her dogs Tinker, Bonnie and Patch and cats Blackie and Katie after she had gone.
And in the High Court today Deputy Judge Charles Hollander QC rejected a challenge by the animal charities to her change of heart and said Mr King was entitled to the house in Kingscroft Road.
He said Mrs Fairbrother, a retired policewoman, who died in April 2011 "adored animals" and "had a variety of cats and dogs in her property."
In an earlier 1998 will left her property to various animal charities, The Chiltern Dog Rescue, The Blue Cross Animal Shelter, Redwings Horse Sanctuary, The Donkey Sanctuary, The International Fund for Animal Welfare, and The world Society for the Protection of Animals.
But four years before her death her nephew moved in with her to care for her.
She left notes and a purported will leaving him the house. He claimed she made a donatio mortis causa - DMC - leaving him the property and handing him the deeds before she died saying: "This will be yours when I go, or similar words," said the judge.
The judge said that Mr King had a "somewhat chequered career", was twice made bankrupt and given a 12 month prison sentence for acting as a company director while disqualified.
The charities claim because he had shown disregard to the niceties of law and honest behaviour he was unreliable and his evidence should not be accepted.
But the judge said there was corroborative evidence that Mrs Fairbrother was seeking to leave her property to her nephew.
The charities claim there was evidence she was suffering from the delusion that one of her cats had gone missing when in fact it died some years previously.
But the judge said: "The evidence did not in my view come anywhere near justifying a conclusion that June did not, when she acted in the manner relied upon by Mr King, have capacity to make a gift of her property."
He said Mr King, who has continued to live in the property since his aunt’s death was entitled to keep it.