Either you or her mother will just
have to take care of the basic hygiene. Please make sure you make her brush and rinse her mouth before she goes to bed at night. Try to avoid giving her milk or anything else to eat or drink after that. Get her to rinse her mouth immediately after she gets up in the morning. And then ensure she brushes her mouth in the morning as well. Also, please check her teeth to see if there are any cavities
in any of her teeth or see a Pediatric Dentist
for the same.