Name our son after my husband?

Here’s the thing... I have always thought it would be cool to name a boy the second, so same exact name as Dad. My husband said he thought about it too...

Well my husband has two kids from his high school GF, two boys.

If our first is a boy is it weird to name him my husbands name, the second?

Is this rude to his eldest son?

Just want opinions...

His sons have grandpas middle names and just random first names.