Son Paul Cooke was jailed for almost 30 years for a robbery and knife attack that led to the death of Ronald Smith, in his 60s, in West Bromwich.
Colin Raymond Cooke, 62, who was jailed for seven years, has had his term increased to 11-and-a-half years at London's Criminal Appeal Court,
He had been convicted of conspiracy to rob and assisting an offender.
The father had been jailed for seven years at Wolverhampton Crown Court in May this year.
Paul Cooke was one of several men who plundered Mr Smith's house in Cottage Walk in May 2015. Others involved in the raid have not been traced.
A man who helped his son plot a robbery, during which a man was killed, has had his jail term increased.