Selena Gomez Looks Happier, Healthier Than Ever on Set After Kidney Transplant News

Selena Gomez looks happier and healthier than ever on the set of Woody Allen's new movie ... but that's understandable after her kidney transplant news.

Selena was seen back on set Thursday for Allen's new untitled flick, in which she has a role, and she was cheesin' wide after news broke she had gotten a kidney transplant earlier this summer.

The grin is probably coincidental, but in light of the announcement -- it also speaks volumes to how badly she needed the procedure to keep doing what she does best ... entertaining the world.