**LOS ANGELES, Jan. 19— **Philip Crosby, one of Bing Crosby's sons from his first marriage and an entertainer in his own right, died last week at his home here. He was 69.
He was found dead last Tuesday by his family, coroner's officials said. The cause was a heart attack, they said.
Bing Crosby had three other sons from his marriage to the former jazz singer and actress Dixie Lee, who died in 1952: Gary, Lindsay and Dennis, Philip's twin brother. All have now died. The four brothers had mixed degrees of success in show business. In the late 1950's they teamed up as the Crosby Boys, a nightclub act, and performed in Las Vegas and elsewhere, including their father's television programs.
Philip Crosby's subsequent show business career was brief. He made some recordings and had small parts in films like ''Robin and the Seven Hoods'' and ''None but the Brave.''
He made sporadic stage appearances, and told People magazine in 1983 that his last gig was at an Elks Club party in Burbank. He had been married four times by then. Bing Crosby died in 1977 at 74. Lindsay Crosby committed suicide in 1989, and Dennis Crosby killed himself two years later. Gary Crosby died of complications of lung cancer in 1995.
Philip Crosby is survived by his four children, Mary Elizabeth Crosby, Dixie Lee Crosby, Flip Crosby and Philip Crosby Jr.; and three half-siblings from his father's second marriage, to Kathryn Grant: Harry Crosby, Mary Frances Crosby and Nathaniel Crosby.