Michael J. Fox posts rare throwback photo of his son for 33rd birthday

Michael J. Fox is one proud papa.

On Monday, the “Family Ties” star posted a throwback photo of son Sam in honor of his 33rd birthday.

“Happy 33rd, Sammy. Unlike hockey player’s teeth, yours grew back,” the actor captioned an old picture of his son in what looks to be a Boston Bruins jersey.

“Love you, buddy. Happy happy. I’m proud to be your Pops.”

Fox’s wife and Sam’s mother, Tracy Pollan, also marked the occasion with her own post.

“Happy birthday @palekidd. Paris looks good on you! Could not love you more,” she wrote.

“Our Sam. Lookin Euro-Fly on his birthday😎 So much love,” Fox wrote in the comments.

In February, Fox and Pollan’s twin daughters, Aquinnah and Schuyler, turned 27 and the “Back to the Future” icon celebrated on Instagram with a series of throwback pictures, as well as more current shots.

“Twice the love, a hundred times the laughs,” he wrote. “Happy birthday to my beautiful girls. I love you so.”

Fox and Pollan met while she played his girlfriend on “Family Ties.” They married in 1988 and are also parents to daughter Esmé, 20.

On Mother’s Day this year, Fox posted a picture of him and Pollan with their kids, while complimenting his wife on the job she did raising their children.

“Our children are beautiful, sensitive, intelligent, empathetic, independent, compassionate, adventurous, lovely people,” he captioned the photo. “That’s your fault. We all love you so much. Happy Mother’s Day.”