A first child who is so adorable, mild mannered, and easy to care for that they trick their parents and other adults in their life into having more children, only for it to be revealed that most children are considerably more difficult to care for
"We thought parenting was super easy, but it turns out that Betty was a propaganda baby."
"I know meeting Cole has your uterus revving, but be careful - he's a propaganda baby "
A propaganda account is an account on a social media platform, usually Twitter, that has no intent on spreading propaganda, instead opting for posting and reposting about a specific topic, occasionally with the intent of making said topic their favorite in its overarching genre, species, etc. Most prominent with Pokémon.
Person 1: "Have you heard Propaganda Machine's new self-titled EP available on all streaming services?"
Person 2: "No."
Person 1: "You really should, it has some bangers on it. My favorite song is The Scarred Domain."
Person 2 (after listening to it): "Personally, my favorite song is Imperial Democracy."