A.C.
My daughter is 6yrs old and happy with farting too. It is the age and stage for it (until about 10yrs old). My daughter pretends to do them! Just to gross me out!
My dad did many terrible stinky farts throughout his life and still does today. He never went to the doctor about it and we just had to try to steer clear. You might want to see a doctor if it's terribly stinky. So maybe its diet or maybe it’s the person.
Good luck!