My husband wants to be surprised about the gender

Diamond

So tomorrow is the "big day" me and the kids have been waiting for. We are supposed to find out the gender of the baby, my husband decided at the last minute he doesn't want to know until the baby is born. I'm literally dying and I want to know and the kids want to know because I have a daughter and a son. My daughter wants a sister so bad and my son wants a brother. If we find out I know me and the kids will eventually ruin his surprise. He's always difficult