While I agree 100% with Shade, I do want to add that you need to cut them a little slack. Dogs like stability. They like constant. They aren't misbehaving because they are angry that you left them. Or they aren't deliberately blowing you off in an effort to establish their leadership. I'm sure they are stressing a little with new change (again). As young pups the best way to burn that stress is by acting out. Then add that at your parents house they didn't have the same boundries you created for them. So it's got to be a little confusing for them.
Before I started cracking the whip, I'd burn off as much energy as I could. Tire them out. Go back to NILIF. Go back to throwing puppy parties as rewards. Go back to using the same training tactics that you used and THEY are used to. Just don't provide any grey areas for them.
Hondo Von Dopplet L Bauernhof "Hondo"- GSD
Lilie's Tug McGraw "Tug" - Golden Retriever
Maggie - Mini Dachshund (Rescue)
Lonestar - Texas Blue Lacy
Funyon, Ashe, Soot - Barn Cats
Scooter /1/2 Arabian, Shadow, Katie / APHA