Michael J. Fox Melts Hearts With Sweet Photo of Rarely-Seen Son in Birthday Tribute

Michael J. Fox

Michael J. Fox is wishing a very happy birthday to his only son, Sam Michael Fox.

Sam, who is the Back to the Future star's firstborn child with wife Tracy Pollan, turned 35 on Thursday, May 30, and he was honored with a special birthday tribute from his famous dad on social media.

Michael, 62, shared an intimate photo of Sam blowing out his birthday candles at their home while sitting in front of a large chocolate cake and what looked to be a celebratory glass of bubbly.

"Sam, what a trip it's been," the proud dad wrote in his Instagram caption on Thursday. "From the boy who had questions about everything to the man who has so many answers and still more questions. I love you."

"Oh yeah, thanks for all the laughs. You are my best friend and only son," Michael added, before concluding the post with a simple, "Happy birthday!"

Sam replied to his dad's sweet post by leaving a message in the comments, telling the Family Ties alum "Aww love you!! ❤️❤️❤️."

After tying the knot in 1988, Michael and Tracy welcomed their first-born in 1989, before going on to have three daughters: twins Aquinnah Kathleen Fox and Schuyler Frances Fox, 29, plus their youngest child, Esmé Annabelle Fox, 22.

Now, their eldest child is about to start his own married life after popping the question to his girlfriend earlier this year.

Back in February, Sam took to Instagram to share a photo of his fiancée's new diamond ring during a snowy trip to South Woodstock, Vermont.

"LFG!!" he captioned the joyful post at the time, while tons of fans flocked to the comments to send their congratulations.

"Love you both!!!! ❤️❤️❤️" his mom wrote to the bride and groom-to-be.

Next: Michael J. Fox and Wife Tracy Pollan Can't Stop Smiling During Courtside Date Night at Knicks Game