Sibling name for 3rd

[name_m]Hi[/name_m] all! We have two boys [name_m]Weston[/name_m] and [name_u]Emerson[/name_u] and are due with our 3rd. Unsure if its a boy or girl but need help with names that flow with the brothers. Dosent need an ON ending. I personally like [name_m]Marshall[/name_m] for a boy and [name_f]Gretchen[/name_f] for a girl. Thanks!