What is a stepbrother?
A stepbrother is the son your step-parent brought from another relationship. You share no parent and no blood — your parent married his parent, and that marriage is the whole connection. That separates him from a half-brother, who shares one parent with you. A child your parent and his parent have together is your half-sibling.
Relationship
Stepbrother
- You
- Your parent
- Their spouse
- The spouse's son
From the other side, you are their step-sibling.
Step relationships run through a remarriage, not a shared ancestor, so the ancestor chart can't draw them.
The calculator below works out blood relationships through a shared ancestor — use it to explore the rest of your tree.
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This relationship sits outside the shared-ancestor model, so the card above carries the answer and the calculator opens in its default state. Work out any blood relationship with it, or open the full relationship calculator.
FAQs
What's the difference between a stepbrother and a half-brother?+
A half-brother shares one biological parent with you; a stepbrother shares none — the connection is your parent's marriage.
Who am I to my stepbrother?+
Their step-sibling.
Does the calculator store my family details?+
No — it runs entirely in your browser. Nothing you enter is uploaded or saved on our servers.
Start with one relative and see what comes back.
Add what you remember and AncestorIQ searches for the rest. Free to build your tree for as long as you like.
No credit card needed. Your tree stays yours.
