My father-in-law will retire next month.
A man who raises a child as his own without being the biological father. Less common than father-in-law.
He was raised by his foster father from a young age.
A man who is married to one's biological mother but is not one's biological father.
At first things were awkward with my stepfather, but now we get along well.
Next week I'm going to meet her father-in-law for the first time.
After getting married, we ended up living together with my father-in-law.
My wife works while also taking care of her father-in-law.