My twin brother and I are named Henry and Sarah, and my mom and her twin brother are named Nicholas and Deborah. No alliteration or anything cute like that.

Our family is not into cute.
Funny story, though. One time I was talking to my very wealthy friend Mike, and he told some story about another rich family and their kids, all of whom had names starting with (I think) J. I said, "I think it's so funny how crazy rich people always give their kids names starting with the same letter."
He said, "Sarah, what's my brother's name?"
Me: "Matt..."
"And what's my sister's name?"
"... oh crap, it's Marilyn, isn't it?"