In Rogue One, Cassian and Jyn went to Jedha in order to meet someone who could take them to Saw Gerrera.
Cassian: I had a contact, one of Saw's Rebels. But he's just gone missing. His sister will be looking for him. The temple's been destroyed, but she'll be there waiting. We'll give her your name and hope that gets us a meeting with Saw.
They never got a chance to meet her, before the Gerrera's gang found them. She probably wasn't at the headquarters either; all of the gangmembers seemed to be males, and no one approached Cassian during his captivity. So, who was she, why would she stay at the temple, and what happened to her (and her brother)?