9 yr old ds pants smelling of wee

[PJ67]

Does anyone else have this? I don't think he's wetting himself but his pants are regularly smelling. My 6 yr ds never has this. Ds seems to wipe himself properly but I'm not sure if he's waiting till the last minute to go to the toilet.
He had a spinal dimple at birth that the doctor said was ok but now I'm worried I case he has some kind of spinal problem as I tend to be a bit of a worrier! Any ideas?

My 8 yo does this! My 5 yo ds does not! With ds, it's always either that he literally waits for the last second to dash to the loo or he's in such a rush to wee, he starts pulling his pants up without quite wiping his willy properly. Last summer hols I made him go try for a wee at regular intervals whether he felt like it or not so he wasn't leaving it till the last minute. And nowadays I impose a 15sec wee time (only for weeing. That doesn't include washing hands etc) and as long as he remembers/i remind him to count to 15, he doesn't get damp pants. It's just rushing! I sound horrible making these rules but I'm really not! Promise!