What happened to Donna Douglas son?

Donna Douglas, best known for her role as Elly May Clampett on "The Beverly Hillbillies," had a son named Danny P. McGowan. He was born in 1963, and while not much is publicly known about his personal life, he has occasionally appeared in the media discussing his mother and her legacy. Donna Douglas passed away in January 2015, and Danny has been involved in preserving her memory.