Sometimes kids feel like they're competing with you for time and attention with their parent. On occasion they need focused time with their parent without you. It brings stability in the midst of a lot of change. So, give your spouse your blessing to spend one-on-one time with their kids. Also, be involved in some family activities, but bow out of others, especially when noncustodial children come and only have a little bit of time. This diminishes competition and shows you to be a safe person.