Bridget Moynahan is celebrating her former Blue Bloods co-star (and onscreen father) Tom Selleck, who turned 81 on January 29. “Happy Birthday to the best TV Dad!” the former model captioned a photo of herself and the Magnum P.I. From 2010 to 2014, Moynahan and Selleck starred in the fan-favorite drama about a family with deep ties to New York City law enforcement. Selleck also got a special shout-out from Donnie Wahlberg, who played Erin’s brother Danny Reagan on Blue Bloods. Tom Selleck!” he wrote on his Instagram Story.