An entire sibset? Definitely not. I think I would avoid even two siblings having the same initials. I could see using the same starting initial if I truly loved the names, but still, unlikely.
I don't have an issue with the initials EJ.
What I'd name 4 girls with EJ initials if I had to:
1)
Eloise Juliette2)
Evangeline Jacinthe3)
Estelle Jacqueline4)
Eulalie Josephine
If I had to select the same initials, I'd probably do some combination of MC just because that would be easiest for me.
1)
Margot Cosima 2)
Madeline Claire3)
Matilda Charlotte3)
Miranda Catherine
♥ Samantha ♥