Andrew Koenig, 41, who co-starred as "Boner" on the 1980s sitcom "Growing Pains," was last seen in Vancouver on February 14 after neighbors said he sold all his possessions in Los Angeles.
"He's been depressed," his father, who has a degree in psychology, told local ABC television station KABC. "He's trying to get ahead in this business and he's been working at it a long time."
Koenig, 73, who played Starfleet officer Pavel Chekov on the original "Star Trek" series and the first seven feature spin-offs, said drugs were not an issue.
Andrew Koenig, who last telephoned his parents on February 9, did not catch his return flight to Los Angeles a week later.
Koenig, who has posted additional details on his website, said he and his wife would fly to Vancouver on Tuesday to join the search.
Andrew Koenig's show business friends also sent Twitter messages seeking information about his disappearance.
(Editing by Jackie Frank)
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