How old is your DDIL?
Are there children yet in the family?
If she has, say, more than three kids, you and she both may find that a really big tree skirt might be just the thing for all the gifts kids receive at Christmas in most households!
And when the tree is first decorated and is without many packages under it, maybe a small village scene, a creche, or a miniature train set could be placed on it.
Jan in VA