Just a quick thought on tethering.
I have heard some folks mention tethering their birds at such a young age. Be careful with this. It is my opinion that creating frustration in a young imprint is possible a basis for aggression. You can contain the bird with a taller box, giant hood or other do like I do and let the bird wander. It needs to explore and flap and do what it does. If you choose to tether, why not take the bird into another room to tether them. That way they have no one to place the blame on. Just my opinion. I have been wrong before...