What are the most difficult challenges a step parent faces in gaining the trust of their new children? Do share.

I'm not a step parent, but I have friends who are. The most important thing is not to deny or deride the child's other biological parent and instead, acknowledge the bond between the child and parent. The most difficult part is having to discipline the child and hear something hurtful like "You're not my mother! Don't tell me what to do!" It's better to start off as a friend and keep very calm in order to gain their trust.