Tom Cruise's Daughter Bella Approves of Dad's Collab with Lady Gaga

Tom Cruise's new friend/collaborator, Lady Gaga, has gotten the seal of approval from one very special fan ... Tom's daughter, Bella, who -- SHOCKINGLY -- is 29 years old!!!

Gaga posted a photo on Instagram Tuesday, kissing Tom on the cheek, thanking him for coming to the show .. and Bella was quick to like the pic.

Bella has kept a low profile over the years. She's been estranged from her mom, Nicole Kidman, but apparently has maintained a relationship with T.C.

Nicole and Tom adopted Bella and her brother, Connor, back in 1995 while they were married. As you know, that marriage disintegrated in 2001.

Tom and Nicole shared custody for a while, but the relationship between Bella and Nicole was strained ... reportedly over Scientology.

Maybe there's been a shift, because Bella has been liking some of Nicole's Instagram photos lately.