updated 02/22/2010 AT 6:00 AM ET
•originally published 02/21/2010 AT 6:00 PM ET
On Feb. 16, Walter Koenig received a note from his son Andrew, which caused his father to grow concerned about his whereabouts.
“He sounded despondent,” says Walter, who spoke to PEOPLE from his Los Angeles home. “Nobody has seen this [note] but my wife and I.”
Andrew Koenig, 41, who starred as Boner on the late 80s sitcom Growing Pains, was set to arrive in Los Angeles on Feb. 14 after a trip to Canada, according to the Vancouver Police Department.
“He went to visit some friends in Toronto and after there, he went to Vancouver,” says his father. “It s a place where he felt very comfortable. He lived there for a few years.”
Andrew still hasn t returned to his Venice, Calif., residence. His father says there wasn t a specific situation that would ve prompted his disappearance.
“I think it s something that has been a part of his makeup for a long time. There s no single trauma. There s no episode. There s nothing of that nature,” says Walter, who added that drugs were not an issue.