I don't want to say what my kids names are, because then that would totally out me! So I'm going to give you a for-instance.
Let's say my DC are called Cleo and June at the moment. Would it be weird to name third DC something like Milo? Two of their names would rhyme, one would stick out.
Even the one not rhyming aside, is it a bit weird to have two names rhyming anyway???
(Like I said: these aren't their names, just examples of the same sort of thing!)