Jen's a Good Samaritan

Brad Pitt and Angelina Jolie may get all the attention when it comes to their charitable work, but Brad's ex, Jennifer Aniston is also helping others, one child at a time!

Besides her scheduled Sept. 5 appearance at the Stand Up to Cancer Telethon, Jen recently shot a PSA for St. Jude's Children's Research Hospital.  And on Aug. 7, she quietly slipped into the 5th Annual Friends of El Faro Benefit for the Casa Hogar Sion orphanage in Tijuana, Mexico.

The star donated two of her own purses:  A white Tod's bag and a brown Henry beguelin, to the auction.

"She also signed them 'With love, Jen Aniston,'" a partygoer tells OK!.  "The cause of children is very important to her.  She doesn't make a big production of it, but you can tell she really cares."