Siblings are Evelyn Kathleen and Graham Harold (Kathleen and Harold are both family names). Girl name for this baby is Mae Elizabeth.
Ideas on the list right now:
Miles Willem
Miles Greyson
Miles Gavin
Miles David
Miles Parker
Miles Ryan
Miles Benjamin
They're all fine, but none of them have been a "That's IT!" for us. Well, I like Miles Willem, but H is "eh" about it. Any other ideas?

Evelyn (3.24.10),
Graham (5.30.13) &
Miles (8.28.16)
Re: Middle names for Miles?
Unless you're a big jazz fan. I mean, Miles Davis and Charlie Parker are both some of the best that ever played.
I don't think it's a deal breaker though. I'm probably the only weirdo who thought of those thinks. Miles Ryan sounds nice. I don't personally care for Willem because it sounds too much like William and I feel like there's bound to be a little confusion there, but again, not a deal breaker. I also think Gavin sounds nice with your other children's names.
of yours are. I like Greyson and Gavin the best.
Evelyn (3.24.10), Graham (5.30.13) & Miles (8.28.16)
Miles Augustus
Miles Theodor
Miles Samson