i think as time went on, they managed to sway Guwon's thinking into kids being like, future insurance? Train them while young so when they're old enough they can join like the hounds or something. That's genuinely my thought. Given the kids' ages, they could help with smaller chores around town, teach them how to read and write and soon they can help others too? Just a guess.

whats up with the kids? the whole point is that people have to show their worth so why would guwon save three random kids bruh maybe i missed part of the plot but it seems random