My child is 7 years old ans she has this bad snore since she was 4. what do i do about it?

See pediatrician: Your child may have enlarged tonsils, tongue or reduced size air passage that needs to be evaluated as this may be restricting air flow, thereby causing the snoring.

see an ENT: Snoring by itself is not necessarily dangerous but it can be associated with obstructive sleep apnea, daytime tiredness, poor school performance, bedwetting, and other behavioral problems. You should have her evaluated by an ENT to consider what might need to be done.