I love
Penelope &
Eleanor as sisters!!! That's so cute! So sweet, old-fashioned yet classic and beautiful!
Penny &
Nora are cute nicknames. I'm not sure about
Asher for a brother,
Ephraim is cute but I'm not sure it goes very well. You should propably go with something a little more classy like, Not so deeply Bibical, something to fit more with the style of
Penelope &
Eleanor.
What about:
Sebastian,
Dominic,
Edmund,
Lewis,
Jonathan,
Thomas,
Theodore, or
Simon
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"There is nobleness in the name of
Edmund. It is a name of heroism and renown; of kings, princes, and knights" -
Jane Austen, Mansfield Park