If your goal is for your daughters to be able to handle the birds as pets, then it is best for each bird to have his own cage. When they live in a group, they will prefer each others company and will be very hard to tame and handle. Also keep in mind that having a pet bird is a big commitment – you need a large cage, plenty of toys, nutritious diet and sometimes veterinary care. All of this can be very expensive compared to the original cost of the bird. If this bird is to be a pet, I would suggest one bird for the family to share. They are not simply a pretty bird in a cage – they need daily enrichment and a stable environment. Make sure your girls are ready for a long term commitment as it is natural for children to want something on a whim and tire of it if it isn’t what they thought it would be. Birds are not for everyone – they take a lot of work to keep them happy and to keep the cage clean – this is a daily job. While the bird or birds may be for your daughters, it is the adult’s responsibility to make sure the bird has fresh food and fresh water daily – if a child forgets to feed a small bird for even one day, this can cause the bird’s death. Dirty water or a dirty cage can make a bird sick, which means a costly vet visit.
Now if you want birds to share a cage, and have each others company without being handled, then first you do need a very large cage. An odd number of birds is generally not a good idea, even if they are all the same sex. You end up with two pairing off, and picking on or fighting with the odd bird. So the short answer on that is I would not recommend having 3 parakeets in one cage.
Before you promise to get them a bird or birds, please do some research on the internet – try pet bird forums with posts from bird owners. Someone selling a bird may make it sound easier than it is. Possibly try to find a parent’s forum and ask if anyone has pet birds and children. I’m not saying a bird is not right for your family, just be sure it is before you buy one. If this is their first small pet, another pet to consider is a guinea pig – they make great pets for kids, come in a variety of coats and colors, and their care is more simple than caring for a bird as long as you feed the right diet and buy the right enclosure. And they will definitely be easier for a child to handle and pet.
Thank you for asking Lafeber,