Christmas pregnancy announcement ideas, HELP!!!

So I bought a shirt for our son that announces our baby's arrival in July. We're going to tell my in-laws on Christmas eve but can't decide how to do it...

Idea 1: walk in with him in the shirt with a coat on and ask his grandma to take the coat off.

Idea 2: have someone open it during the white elephant gift exchange (the only thing my husband doesn't like about this one is his mom might not get the gift)

Idea 3: saying I'm putting his pajamas on but change him into that shirt and have him come out in it.

Any more ideas??? I don't really want to just wrap it and give it to his mom. That's kind of typical.