My sister and I always check with our stepfamily to see if thier families are available for a family function before we set the date. We feel that it is important for all of our immediate family members to be a part of a family function. This is hard to do because two familys are divorced and the visitation on weekends gets tricky, but we always manage to get it done so all the kids can be there. They however do not offer this same consideration to us.