Rob Gronkowski Celebrates Birthday with Bikini Dance from Camille Kostek

Rob Gronkowski turns 29 today -- only 40 more years until his favorite number -- and he's celebrating with an insane trip to Jamaica with his bikini model girlfriend.

Gronk and Camille Kostek have been living it up at some super fancy resort -- eating fruit, hiking to waterfalls and busting out some sexy bikini dances (thanks for that, btw).

Gronk seems to be in a good place -- as you can see at the end of the dancing video.

The two have been connected for years -- they were serious, then took some time apart ... but now they seem to be in full swing.

No word if a ring is in Camille's future ... but it sure seems to be headed in that direction.