The biggest issue here is that why aren't kids oilies made to the same spec as adults.
When my boys were younger I had an impossible task in trying to find high-quality technical oilies for them.
Yet if you think about it, Dad now has his high tech gear , Mum has hers (and after many years they make them so they almost fit for women), but the kids, who feel the cold, damp,wet etc much more than the adults can't get decent gear!
AND if you think about who is going to get hypothermia first, Dad with a decent beergut, Mum with several layers of what she keeps promising herself she'll diet off eventualy - or the kids with no fat, no reserves and usually who are not strong enough to do much on the boat - so don't even get the blood going round!
Its not just the oilies either, but the thermal layers underneath, just try buying them for an eight year-old and see how far you get!
No wonder so many kids get put off sailing.