"And you, fathers, do not provoke your children to wrath, but bring them up in the training and admonition of the Lord." (Ephesians 6:4)
Children can be quite a challenge to the marriage relationship. A wise wife will support her husband's leadership in the home as much as possible, and will praise him for his fathering skills. Negativity makes a man feel like a failure, and may make him to want to give up.
Does your husband discipline your children wisely? Does he show them love and encourage them? Does he take an interest in their activities and dreams? Does he spend time with them? Does he take part in developing their character? Praise him for these important life skills.
If you don't have children, is your husband positive and encouraging around other people's children? Let him know that you have noticed.
If your husband does not experience positive relationships with children, you will need to figure out why. Perhaps he had negative experiences as a child with his own parents, and needs to learn how to respond. Perhaps you can lovingly and patiently show him how to parent--while still maintaining his authority in the home.