Keen’s hack is practical and sentimental at the same time:

Now that my twins are three, we finally bought our first Christmas tree. We bought it about a week after everyone else, apparently, and by the time we got to Target the shelves had been picked clean and the only Christmas tree skirts left were the fancy ones that cost $50, which seemed excessive. My husband suggested using our boys’ “Baby’s First Christmas” blankets, which they’re really too big for, but I was dreading putting them away because they have such sentimental value. Knowing I’ll bring them out every year and see them under the Christmas tree makes me very happy.

Related: Use outgrown Christmas outfits as holiday home decoration