My DSS's mum just sent me this :
www.ivillage.com.au/relationship-with-stepdaughter/
In our case the child is a boy but her point was that this is what we have. It wasn't always so rosy and it's taken 10 years but we've all persevered and this perfectly describes where we are now and have been for a good while.
Not being smug, believe me, I've had some hard times being a step parent - just think it's nice to hear that it can all turn out well, with a lot of luck and a good dose of common sense all round.