Mine calls it 'poppyseed' because one of the first pregnancy things I looked at said that's the size it was when we found out. He's even got a whole category of pregnancy and parenting subreddits saved under that nickname on his reddit account.
Meanwhile I call it a troll baby because she keeps trolling me by making me feel icky.
We're excited as we have our first u/s tomorrow and he looks at me and says, 'you know we're not going to know if it's a girl or boy yet.' And I said, 'yea, I know, but maybe we can see if it has horns.' 
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