My SO's parents are having their annual pumpkin carving Friday night and of course he wants to tell…

My SO's parents are having their annual pumpkin carving Friday night and of course he wants to tell everyone after our ultrasound that afternoon. His idea is cute, but I am just scared of how everyone will react. I also feel that it would be respectful to tell his parents first and then everyone else. Plus I'm only 6 weeks, I feel like it's a bit early to be announcing.