When my daughter was 7... she and her friends loved, Pet Shop toys!
They did not like Barbies.
Legos? Well, you should make sure if the girl likes that or not. Per my daughter and her friends, they either like it or not. My daughter likes it.
Some of her friends, girls, were not into it.
Crafts Kits... are also very, popular and well liked.
Books too. Or a gift card for a bookstore, plus something else.
And no, just because you give a gift card to one child, it does not mean that the family then has to take ALL the kids to get/buy something too. My kids are not like that. If they get a gift card as a birthday gift, then they can get something. The other sibling does not expect me to buy the other sibling something too, just because one of them is using their gift card.