Have your Will drafted to make your intentions clear. If you are BOTH owners on title of the house, the survivor typically owns the house 100% But if you are owners (each as to half - also known as tenants in common) then each of you can dispose of your half as you see fit. Sit down with an Estate Planning attorney. See 'Find-A-Lawyer' at the top of this page.
My answer is based on the limited facts presented. It doesn’t create an attorney-client relationship. Use the ‘Find-A-Lawyer’ search engine at the top of this page and follow proper legal advice.
If the husband is not the father of the three children they you need a will. If he is the father of the 3 children and you bought the house together then he has a community interest in the house and will also have a usufruct over the half inherited by the children. In that case you do not need a will as his ownership interest and usufruct will protect him. Otherwise you need a will.
Every situation is different and you should consult your own attorney to go over all the particular facts in your case. The answer given is only intended to provide general guidance regarding rights and responsibilities.