The series of pics included photos of their matching spoon tattoos, which they got last year, as well as a cute pic of them cuddling on a couch while Jackson rocked a pair of bunny ears, and a snapshot of the two of them wearing custom matching plaid overshirts, with "Mack" and "Paris" written on the back.
"Happiest of birthdays mack attack," Jackson wrote in the caption. "I love you so so dearly and keep you very close to my heart. Always."
"I'm going to warn you now, I am very protective of her so just look out," the actor said when Maron broached the subject. "I am a very open book when it comes to things but like with her, she is beloved by me."
When asked simply how Paris is doing, the Home Alone star answered, "She’s tall, and beautiful and smart. It’s great."
Check out the video below to hear more from the interview.