Hi and welcome ,
Your daughter presents with symptoms of acute pahryngitis. It is often bacterial or sometimes viral infection of the throat mucous membrane
leading to inflammation , redness , pain ,sore throat
, difficulty in swallowing , fever , enlarged lymph nodes , white patches in the throat and ulceration.
Swelling in the gums can be associated with bacterial infection due to improper oral hygiene
, accumulation of plaque and calculus .
i suggest you to have amoxicillin with clavulanate 325mg two times daily along with and analgesic for sore throat. mouth gargling with lukewarm saline water or antiseptic mouthwash like chlorhexidine
gives soothing effect to throat and helps in healing.
consult a dentist
get the thorough scaling of gums and root planing to of teeth which will subside the gum swelling.
i hope this helps , take care.