DS is 3.5 and needs 3-4yr old trousers (or jeans or joggers) for length but 18-24mths on the waist. He just had a growth spurt and looks like an urchin so I've had to get rid of the few 2-3yrs jeans that were sort of acceptable and I need to get more. Next are the only ones I can find with those tabs and buttons inside the waist. Any trousers I see with what look like drawstrings are just decorative. I need to go on a hunt at the weekend, where should I hit up?