Chronic tonsillitis is a condition where paired lymphoid organs called as tonsils get recurrently infected causing frequent attacks of throat pain, fever and painful swallowing. In childhood it may be accompanied by adenoid hypertrophy where child can have nose blocks, mouth breathing and snoring.
There are hardly any absolute indications for surgery of tonsils and only absolute indication being obstructive sleep apnoea. Grade of tonsil size has to relation to severity of infection.
If your child is suffering a lot from recurrent infection then surgery can be done. If you don't want surgery there is no harm in leaving tonsils alone and giving antibiotics and other drugs during infective episodes