Hi J. :-)
Under the tree as soon as they are wrapped.. LOL! that is my daughter's way :-) when I was growing up.. Santa brought ALL of the gifts... so when we went to bed there was nothing and when we woke up.. woo hoo!
But.. my daughter LOVES to see the excitement of "things to open".. she didn't even care if they were hers.. just lots of "presents" under the tree was fun for her.. so it's ultimately up to you... but in this house, even at age 23.. the gifts are under the tree as soon as they are wrapped.. AND.. my daughter will buy lots of her own stuff.. from "us".. and wrap it herself and she STILL loves them under the tree.. hahah!
hugs,
A. R.N., Energy Medicine Practitioner