What is better? Stepmom or no mom in the home if dad has sole custody?

Consistent parent(s) If dad is custodial parent he shuld be the primary enforcer of boundaries and rules. Stepmom's have to be consistent with the primary parent's handling and defer to them as needed. Many kids in this situation "resent" new stepmom's because they haven't been a factor hereto fore in that child's life if the child is over age 6.