Keep in mind that a lot will depend on how much time and energy you are putting into training your dog. She is still a baby but sounds like she is doing well.
The "stay" is just about consistency, just start of slow, 10 -15 seconds and work up from there. I had a stubborn one, so I had my son hold the leash while I went out of sight for a few times. Eventually she got it...I did do some peaking around the corner as well while I had her in a stay.
As for the recall, this again is about consistency, you must teach her to come, start with a short leash and work you way up to a 30' lunge line. Call her to you, using a happy voice and plenty of yummy treats and gradually lengthen the line she is on. If she does not come when asked you can gently reel her in with the leash using the "come" command.
Leaving socks and shoes alone does come with age, (I still hide socks from one of mine) Try trading her and treat for the items she has picked up, tell her to leave it while waving the treat in front of her, when she drops it, tell her "good girl leave it"
As for the child, you'll need to be more specific...
make sure to have plenty of chew toys around and swap out your arm or leg for an appropriate toy...
I find it is easier for them to learn the desired behavior if you make sure they understand what it is you want, I always repeat the commands over and over again.
Good luck hope this helps