Tonsilitis is an infection of the tonsil. it could be from infection of the mouth or the nose. If your child has tonsillitis he or she needs to be examined by a pediatrician.

Bad breath or "Halitosis" in children can occur due to several reasons like poor oral hygiene, mouth breathing, tooth decay, gum disease, infections in the mouth, bacteria on the tongue, dry mouth, tonsil stones, foreign objects in the nose and some medical conditions.
Start with improving the child's oral hygiene by ensuring she brushes twice a day and making sure she brush the tongue as well. Take the child to see a dentist to exclude oral infections, decay, gum disease etc. If it's still persistent you may need to see a paediatrician as well to exclude other causes'.

A tonsillectomy is an operation to remove the tonsils. An adenotonsillectomy is an operation to remove both the adenoids and tonsils. You need to go back to the hospital for proper eveluation