Well well. In the end I looked it up … apparently
"A gender-reveal party is an event or celebration had during pregnancy. The primary goal of this event is the eponymous “reveal” of the baby’s sex to the expecting parents, family, and friends."
Not what I thought at all. Maybe for those of you with kids it was obvious.
I assumed, being California, it was something to do with deciding what gender one wanted to be along the lines of “Tales of the City” - lovely mini-series with the fabulous Laura Linney and Olympia Dukakis.
Instead, it’s some poor foetus who is going to live for the rest of his/her life being reminded she/he was responsible for the California Wildfires and came into the world under a pall of smoke.