I was messing with the creation kit and came up with this. I didnt like the children in Skyrim as they look awful, the boys and girls share the same face lol. So I decided to do a test and add a girl into the game. Well the job was simple, I just edited her height and made her a follower.
Rebecca, a girl they found wandering in the wilderness then brought her back to Riverwood Giant Inn to help out with the chores. A beggar armed only with a dagger to protect herself. You can recruit her and have her accompany you on your journey and quests, she's quite capable and can put up with a fight (she's mastered with human melee lvl7) Being the master yourself, you can equip her with your armor and weaponry...

good luck becky!

Note -
All I did was made a full grown character shorter to look more like a child, so I'm not responsible if the user used a nude mod over this girl NPC.
I was not able to take a screenshot for the girl, sorry about that

I can't assign her with a female girl voice, doing that makes unrecruitable for a follower.
I given her the marriage faction attributes, I hope it works as I have yet to test it out myself.
She has a nasty habit of cutting herself when being idle

Thank you kicknnit for the image

TITLE edited for good reasons. Thanks my friend, vexxallarius for your advise. Appreciate it.