Much Healthier Lindsay Lohan Hangs Out With Scary Skinny Sister Ali

Lindsay Lohan showed off her much fuller, post-rehab figure Saturday, ironically on a shopping date with her scary skinny sister, Ali.

Wearing shorts and a loose-fitting shirt, LiLo revealed a very full face, heavier thighs and even a belly.

Ali, 19 and an aspiring model, appeared painfully thin.  Her collar bone and ribs were on full display in her backless halter top.

Linds was behind the wheel of a white Mercedes-Benz convertible for the siblings' shopping trip. After three months in rehab, she seemed to be enjoying the attention of fans and photographers, smiling broadly for the shuttermen.