Raised 3 sons and apparently found out it started with a book in 2005 so my boys would have been 8 and 5 at the time. Never knew about it until I joined Facebook around 2015 or so. Never saw it till I met my wife in 2016 and she had been doing it with her kids for years. It’s one of her few flaws she has, and I wish she would stop with it, but I’m not a jerk so I don’t make my wife stop doing things that she likes and the younger kids like just because I think it’s stupid .