Ash (Engines of War)
From Tardis Wiki, the free Doctor Who reference
Ash was a human boy living on Moldox during the time the Daleks occupied the planet during the Last Great Time War. He had sandy blonde hair. He was good at picking locks and taught Cinder how to do it before he was killed during a Dalek raid later that same day. He was only 12 years old. Cinder rewatched the memory of Ash teaching her how to pick a lock when Karlax and the Castellan used the Time Lord mind probe on her on Gallifrey. Ash's lessons came in useful when she used a bracelet made for her by her deceased brother Sammy to break herself and the War Doctor out of a prison cell beneath the Capitol. (PROSE: Engines of War)