A big concern for parents who are separating or separated is how to manage children’s access to the other parent. The following is a list of things to avoid to help children have good meaningful relationships with both parents:
1. Do not poison the children against the other parent;
2. Do not pry the children to obtain information about or stay connected to your ex;
3. Do not make children feel guilty about spending time with the other parent; and,
4. Do not use access as means to hurt your ex.
http://divorcedmoms.com/articles/5-behaviors-to-avoid-when-coparenting-after-divorce