Sean Penn and Robin Wright Back Together

Sean Penn and Robin Wright are back together in NYC ... although it's probably not a romantic getaway.

The exes, who divorced back in 2010, flew into JFK Airport Tuesday morning, and walked out together. They also left in the same SUV.

Sean does have a good track record when it comes to making peace with his exes -- see Madonna -- but this one seems to be more related to co-parenting.

Robin and Sean's 23-year-old son, Hopper, lives in NYC and recently opened up about a stint in rehab. He's publicly thanked his father for helping him clean up.

So ... mom and dad TLC mission, or rekindling?