Hello, Thanks for joining the forum.

Where are you getting this puppy ?

Seems like most of your questions should be answered by the people selling you the puppy. A lot of is just basic dogs 101 stuff.

I would safely say you have a TON of reading and research to do on the breed if you have a puppy on the way and you're asking basic things like size and brushing.

How have you prepared for this puppy?

Obviously, many of us here have at to offer but the format in which you've listed all your questions is a bit daunting. That's so much information. ...all of which is extensively covered all over this forum.

Hopefully you're already searching around.

The Siberian Huskies for Dummies book is a good place to start reading and making some informed choices about your game plan, which you are behind on already.

Hey Day <?>, first I have a request of you - go to your profile and give us a bit more information on you.  At a minimum, having a name and a location to hang on you helps a lot, of course add your puppies name when you finally have one.

Your two questions - at least the two that *I* see:

1. Since you're only 16 (youngster ) your parents should be young enough to handle all the daily chores that go along with having a puppy underfoot. I presume that they've agreed to the puppy but I have to ask "Are you all aware of the responsibilities that go into raising a pup??" Getting a new puppy and then leaving for theatre practice - leaving puppy and resulting messes - might be disenchanting for a parent. But to answer your specific question, if they're prepared to walk him, etc when you're not available = remember he's your responsibility then the socialization with other humans will be a good thing.
   
2. SIL's 3 year old Husky. AFTER he's had his shots then it would probably be a good thing. Socialization is high on a Husky's needs - most Husky's have never met anyone but friends and it's important that they meet them all (human and canine) favourably. If your SIL's Husky is well socialized then she'll know what's acceptable behaviour between the two of them and when to let the little one "have a break" from the older, bigger, probably rougher adult.
   

If the picture is the one you're bringing home, I'd guess that you've only got a couple of more weeks to prepare everyone for the fun and aggravation of a puppy.
BTW, he's a handsome little devil!!