My son is 7 going on 8 and still poos his pants regularly

My 7 year old son is quite intelligent and very loving and he has a solid and stable home with lots of positive role models in his life.

For some unknown reason he will go months and not poo his pants then all of a sudden he will do it all the time? Then when you ask him if he has poo'd his pants he says no, but we can clearly smell it. He doesn't seem to be able to smell it at all. I am very worried that he will be discovered by the other kids at school and teased for it.

He is often very hands on at school and at home too and has to be reminded constantly to keep his hands to himself. He is not a mean child or a bully and quite often he is reacting to some perceived wrong he feels he has been dealt.

We are not sure if he is suffering from SPD, and he does tick quite a few of the boxes so we will seek a diagnosis with a professional and take it from there.