With my daughter, I did the classic onesie in a gift box. It works because I gave it to my dad the night before his triple bypass surgery. A gift didnt seem odd and it was a wonderful surprise. The onesie said worth the wait because my parents had wanted grandkids for SO long.
This time, Im going to frame and wrap my first sonogram picture and write on the frame Baby Stark and January 2019. Im going to give it to them when we are visiting in two weeks and tell them its a combo mothers day/fathers day gift.