I have kept guinea-pigs for years , never kept rabbits.
Guineas are lovely but they are quite shy and fragile .
Very rarely bite but they do have sharp teeth and they are utterly defenceless. So if they did want to bite you, they could .
They are also quite allergenic if your DC are sensitive to hay or fur.
Question is : what pet do YOU want.
You will be the one looking after it. You;ll be feeding, cleaning, catching, making sure they are safe.
Your DC will most likely get bored . (Look on sites like GumTree - most are 'Kids bored' 'Kids allergy' 'No time to look after them' 'Moving' )
If you don't want guinea-pigs , what about a young cat?
Far more independant than a dog , no hay (but there is the fur)
Or wait till she's older , 8-9 is a better age for a pet, They belong to the household. They can handle them, take responsibility more (though under if your DC 16yo it is your shout) .
My DD was 9yo when we got our first pigs, no we;re down to the last (of 8 over the years) my DD is 16yo now.
I can think of few worse reasons to bring a couple of fragile little animals into your home than "I don;t know what to get my child"