This might be news to you, I know it was news me: I guess Moosejaw has all these jackets for short people. Like really short people. Really short. Upon further investigation, I discovered that said short people are actually this type of people called "children". Weird, I know. Apparently "children" are just like regular people only younger and more apt to have Kool-Aid mustaches.
Anyway, check out kids' jackets (a kid is another word for child, it is also a baby goat, but we don't have goat jackets yet) from top brands like The North Face, Patagonia, and Mountain Hardwear. Not only are there jackets for boys and girls, you'll find some pretty adorable jackets for babies, too. Not that babies need any help being adorable, or anything, I'm just letting you know about it.
Pretty much any kind of jacket you can think of for regular adult people can be made for child people. I know, it's crazy. Check out kid's fleece jackets, like the kid's North Face Denali. You can find the Children's Denali Jacket for boys and girls. Heck, there's even a kids' Thermal North Face Denali for extra warmth on cooler days.
For colder weather, kids' down jackets from Patagonia are probably just the ticket. That's a figure of speech. Seriously, though, check out kids' insulated jackets with either down insulation or synthetic insulation from The North Face, Patagonia, Marmot, and Mountain Hardwear. You might even want to check out ski and snowboard jackets for kids.
There are even kids' rain jackets like Kids' Marmot Precip, Patagonia Torrentshell, and The North Face Zipline Jackets. Raincoats are available for both boys and girls and feature sweet stuff like pit zips, storm hoods, and watertight zippers just like the grown up versions.