Was she injured in her groin? You have not mentioned how she got the bruise
The knot you see under the skin may be due to
as such due to direct impact.
- Infection of the skin
- lymph node enlargement secondary to injury and infection.
Unless one examines, its difficult to tell what exactly the swelling is.
If due to infection, antibacterial ointments
for a week will be of help along with Acetaminophen
orally in a dose of 15mg/kg/dose repeated every 6 hours for pain.
If its persistent and troubles her its better to have a word with your doctor.
hope my answer helps you.
All the best.