Michael Jackson, sister Janet and their seven siblings snubbed their father's 76th birthday bash last month - leaving dad Joe feeling "hurt".
Jackson Sr's disappointment was compounded by a "really bad" impersonator who performed Billie Jean at the Las Vegas bash in place of his most famous offspring Michael.
A source says: "As Joseph was trying to explain why his famous son was missing, this impersonator is on stage singing Billie Jean.
"It was really bad."
Last year, Joseph's 75th birthday celebrations were a markedly different affair - when 1,200 turned up to congratulate him at son Jackson's Neverland ranch in California.