Cassim is father of Aladdin.
He found it when Aladdin tracks the 40 Thieves to their hideout, and learns that his father is actually Cassim, their leader, rather than a prisoner.
![Cassim](http://chill.queryhome.com/?qa=blob&qa_blobid=6779462906061804996)
Aladdin gains entrance into the Forty Thieves by fighting and defeating Sa'Luk in a fight.