IF we had another kid (just curious)...?

We have twin baby girls due in August which we are planning on naming Guinevere (gwen-eve-air) "Gwen" Faith ___and Magdelene (mag-dail-lin) "Maggie" Grace ___ (___is our last name which I don't want to post) Anyway my wife and I were wondering if we had any kids (boy or girl) after them, what sibling name would go well with them. Just Curious.