Step-parents have a tough challenge forming relationships with the children of their significant other. The following should be avoided to establish a good relationship:
1) making negative comments about the ex;
2) inappropriately disciplining the stepchildren;
3) attempting to replace the ex;
4) ignoring the wishes of the ex;
5) Being jealous of the ex.
http://divorcedmoms.com/articles/8-boundaries-stepparents-should-never-cross
