That night, investigators allege, an argument broke out between Arunkumar Ingle and his wife and son Parth in the family home in the 200 block of Chestnut Avenue in Middletown Township.
The wife and son then killed the Boeing Co. engineer, Pennsylvania state police allege.
The Delaware County medical examiner ruled that his death was caused by "crushing blunt-force head injuries with multiple stab wounds to the head and neck," the state police said. His testicles were severely bruised.
An affidavit made available when Parth Ingle, 25, was arrested in December disclosed that the victim was having an affair with a Philadelphia woman.
The elder Ingle planned to fake his death in India, then return to the United States to live with his mistress, authorities said. He would leave behind $3.6 million in life insurance for his family.
According to an affidavit for Bhavnaben Ingle, her son owed, at the time of the murder, $29,000 for a car and $8,000 for a motorcycle and had $5,900 in credit-card debt. His girlfriend had a $220,000 mortgage on the house where they lived together. She also had a $41,000 second mortgage and $12,000 in credit-card debt.
Parth Ingle was two payments past due on his car loan and the motorcycle was in "repossession status," the earlier affidavit said. Parth Ingle lived off of money provided by his mother, who worked at a 7-Eleven in Delaware owned by her daughter's family. Bhavnaben Ingle was arrested as she left work at the 7-Eleven.
In 2003, Bhavnaben Ingle suspected that her husband was having an affair and gave her son permission to install spyware on a computer to record his passwords. Their son then confirmed that his father had a mistress.
Two weeks before he was charged with murder, Parth Ingle was sentenced to two years' probation after being found guilty of using software to get his father's e-mails.
Lawyers for the mother and son could not be reached for comment Thursday evening.
Contact staff writer Robert Moran at 215-854-5983, bmoran@phillynews.com, or @RobertMoran215 on Twitter.