Espresso bars aren't just for grown-ups anymore. Moms and dads in trend-setting New York City neighborhoods have started ordering foamy "babyccinos" for their pint-sized offspring, says Eli Rosenberg at The Brooklyn Paper. "Our children love babyccinos!" says one man with two daughters, ages 2 and 5. Here, a brief guide to this strange coffeehouse trend:

Just what is a babyccino?
There are two varieties. One is simply a tiny cup of decaf cappuccino — a shot of decaffeinated espresso topped with steamed milk. The other is an off-the-menu treat that some baristas will whip up just for little ones, consisting entirely of nothing but frothy steamed milk and foam. Sometimes, to sweeten the deal, baristas throw in a sprinkle of chocolate or cinnamon powder, or a tiny marshmallow or two. They cost up to $2, although some coffee drinkers say they expect a free serving of foam for kiddies when they're ordering several adult drinks.

Who came up with this idea?
The trend appears to have started in Australia about a decade ago. The original babyccinos were of the milk-only variety, which made them a pain to make. "They interrupt workflow, create milk wastage, and can be served at a dangerous temperature to a vulnerable consumer," Australian coffee expert Paul Caligiore tells The Brooklyn Paper. But kids loved them, so parents ordered them, says Caligiore. Now it's "difficult to find [an Australian] cafe that doesn't have them on their menu."

How did the trend reach the U.S.?
Babyccinos drifted from Australia to England, possibly thanks to YouTube videos showing parents making the treats for their kids. Word spread, and parents started asking about them in Brooklyn a few years back. "I think it was from a TV show or something," coffeehouse owner Gemma Redwood tells The Brooklyn Paper. "It's a little weird — but we make it."

Is this safe for kids?
No, this is a "horrible idea," says Jen Chung at Gothamist. Decaf coffee still has some caffeine, which is linked to childhood obesity. Plus, babyccinos are sure to prove a gateway vice, says Paula Forbes at Eater. "First it's decaf espresso, then it's the real stuff, next thing you know your kid's chain-smoking Gauloises. Parents, you've been warned." Well, it's worth the risk, says a parent in a discussion at Australia's Coffee Snobs. "They keep the kids happy so that I can enjoy my coffee in peace!"

Sources: Brooklyn Paper, Coffee Snobs, Eater, Gothamist, Huffington Post