Half Brother vs. Stepbrother
Relationships in blended families can be confusing -- especially to those outside the family who might be trying to figure out the dynamics of a specific family. The Merriam-Webster dictionary defines a stepbrother as the male offspring of your stepmother or stepfather. Your half brother has the same mother as you and a different father or he has the same father as you and a different mother.
1 Stepbrothers Are Bonded Through Marriage
A stepbrother has no biological relation to you. You are related by marriage because one of your parents married one of his parents. This remarriage may have occurred due to death or divorce. You may live with your stepbrother or you may only see your stepbrother because of a custody arrangement. Stepbrothers might not bond in the same way that biological siblings do -- especially, if they were brought together at a later age, according to the article, "Q & A About Step Siblings and Half-Siblings," published on the Break the Cycle website.
2 Half Brothers Are Bonded Through Blood
A half brother is your biological sibling through one of your parents -- meaning that you two the same mother or the same father. This may happen if a parent dies or divorces. You may live with your half brother or he may live with the parent you don't regularly live with. For example, your parents divorced and you live with your mom. Your father then has a son with his new wife. This son is your half brother. You will see your half brother when you visit your father.