Got a 2 year old. He was in one of these guys: Togz UK Ltd
suits that was 9-12 months that fitted him from 9 months till late summer (nearly 2). First one was an all in one suit and it was hard wearing.
He's now in a 2-3 year old sallopette style with a jacket.
Seem very well made. His current ones even have reflective tape on them (looks like a mini 'sailor'...). Delivery good. I believ they are Made in Britian (for now till Scotland gets independance)
Not cheap... but you gets what you pays for.