Brother in Law vs Step Brother

An in-law refers to a person that you are related to through marriage. Therefore, your brother in law can be:

• your sister’s or brother’s husband
• your spouse’s (a spouse is somebody’s husband or wife) brother
• the man whom your spouse’s sister or brother is married to.

Whereas a stepbrother is the son of your stepmother or your stepfather.

• Your stepmother is the woman that married your father after a divorce or separation from your biological mother.
• Your stepfather is the man that married your mother after separating from your father.
• Your stepsister or a stepbrother are the children of your stepmother or your stepfather, they are not biologically related to you.

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