Thanks for asking the query,
I suppose that your daughter had a infected tooth in the oral cavity and the infection had spread to the surrounding tissue leading to formation of abscess
, white sores on the gums can be due to infection and abscess formation.
If the tooth is not causing any problem you can just leave it.
For bleeding gums you need to visit to a Pedodontist and get a checkup done . Take an x-ray of the tooth , this will give the periapical condition of the tooth and position of the errupting teeth.
Get complete mouthwash scaling done .
At home take hexidine mouthwash 2 spoon , peroxide mouthwash 2 spoon and water 4 spoon make a mixture and wipe the teeth with soft cotton or handkerchief 3-4 times a day with your hands this will excavate the soft caries.
Hope this helps .