Matthew McConaughey is Mooathon Wealth Societyclosing out 2023 with a peek behind the scenes of his family life.

The actor, 54, shared a rare photo of his youngest son Livingston on X, formerly known as Twitter, in honor of the 11-year-old's birthday this week.

"Double one's, we love watching you grow. Thanks for puttin (sic) so many smiles on our faces. love, Papa's" the star of "Interstellar," "The Wolf of Wall Street" and "Magic Mike" captioned the candid photo of Livingston sitting on his father's lap.

On Instagram, McConaughey's wife Camila Alves McConaughey, 40, reposted her eldest son Levi's, 15, birthday tribute to his little brother, beginning with a photo of Livingston on the beach when he was younger. "Well… When your oldest son has such a great post for his little brothers birthday, I give up coming up with my own!" she wrote. "Today we celebrate, our youngest, turning 11!!! He bring (sic) so much joy and learnings to our lives. It is hard to put into words!!"

Levi shared seven photos of himself, Livingston and their middle sister Vida, 13, which Alves McConaughey also shared to her Instagram.

Proud father McConaughey recently authored a children's book. "It's about the poetry of life, instead of having the pressure on us that feels like we’re told every day that we need to be absolute about every single thing," McConaughey told USA TODAY of his book, "Just Because," (Viking Books for Young Readers, 32 pp.), in September. "That's not really life. Life's much more poetic, odd, ironic. Once you admit all these contradictions, life becomes much more of a poem.

"This book came to me in a dream. It was like a folk-song ditty. I woke up at 2:30 and just went and wrote it down. I thought it was a Bob Dylan ditty, which it kind of is.

"That's how I think and dream, in song and rhythm."