Congratulations! Your daughter has a lovely name and so does her brother.
Congratulations! Faedra Elise is lovely, and I think it's great with her big brother's name, too. I agree with @mischa - usually the Berries don't love alternate spellings (myself included!), but Faedra just works. I've never liked the look of Phaedra, and I love the family tie with Faedra, and it looks more faerie-like with the "F" spelling! All the best!