Australian MP in feud with family of dead ex-lover

During her 10 years as an Australian federal MP, Sophie Mirabella has acquired a reputation as a strident right-winger.

But her political career may be in jeopardy, following revelations of a feud with the family of her ex-partner, a prominent QC 40 years her senior.

Ms Mirabella, a frontbencher with the main opposition Liberal Party, had a clandestine five-year relationship with Colin Howard in the late 1990s. Not even her family knew about it. She remained close to him after marrying Greg Mirabella, a former Army officer, and Mr Howard made her executor and – his two children, Mervyn and Lesley, believe – sole beneficiary of his will.

Following their father's death at 83 earlier this month, Mervyn and Lesley are considering a legal challenge to Ms Mirabella's management of his estate. According to The Age, they want to know if Mr Howard, who was diagnosed with Alzheimer's in 2008, was mentally fit when he gave her power of attorney. Ms Mirabella, who entered parliament in 2001, was one of six Liberal MPs who in 2008 boycotted then Prime Minister Kevin Rudd's historic apology to mixed-race children forcibly removed from their families.

Sophie Panopoulos, as she was at the time, was 26 and beginning a legal career when she met Mr Howard at a function. He was 66, and had been dean of law at Melbourne University. They began a relationship, and set up home together in Carlton, a fashionable suburb of Melbourne.

In 2000, Ms Mirabella moved to Wangaratta, in rural Victoria, seeking nomination as a Liberal election candidate. According to The Age, Mr Howard lent her his car to campaign in and donated more than A$100,000 (then equivalent to £36,000) towards her campaign expenses.

He later gave Ms Mirabella a substantial sum to help her and her husband, whom she married in 2006, buy a A$695,000 farmhouse in Wangaratta. Mr Howard informed his son that he had cashed in a pension, and it is claimed he also said Ms Mirabella had asked him not to tell anyone about the gift. At that time, Mervyn and his sister already had concerns about their father's mental health. When Mervyn Howard emailed Ms Mirabella to query her acceptance of the money, she replied, telling him she did not expect "that you did or ever will understand Colin's relationship with me".

As Mr Howard's health deteriorated, the Mirabellas helped him to move to a cottage near their farmhouse, where they looked after him. He cut off contact with his children. Mervyn told The Age: "We believe she [Ms Mirabella] adopted a deliberate tactic to split our family."

In a statement, Ms Mirabella – who stands to inherit Mr Howard's A$1m house – said she had not yet applied for probate. She said there was "no public interest in denigrating the memory of a private man".