I don't think they have to start with the same letter, and if I had twins I probably wouldn't do that unless I loved both names, but I think it's cute if they start with the same letter.
I would name them:
Elyse Delilah and
Natalie Elizabeth or
Natalie Delilah and
Anna Charlotteor
Charlotte Elizabeth and
Natalie Reagan or
Rebecca Charlotte and
Charlotte Elizabeth or
Elyse Delilah and
Rebecca Charlotte
I don't really like any names that start with the same letter for a girl, so if I had twins I probably wouldn't name them names that start with the same letter.. actually
Rory and
Reagan are pretty cute, for either boy or girl, as twins.
We love Him because He first loved us.
1 John 4:9