They’re barking up the wrong tree with this one.

One in three millennials has a pet, typically a dog or a cat. And research firm Packaged Facts thinks that pet ownership is so prevalent among the 18-24 set, in part, because millennials think it will help them learn to parent. Indeed, nearly seven in 10 millennials (69%) say that having a pet is good practice for having a family, the research, released Thursday, reveals.

Um, think again, experts say. “The developmental, psychological, financial, and custodial needs of a child far surpass those of an animal by more than a hundredfold, and for a greater lifespan,” says Beverly Hills family and relationship psychotherapist Fran Walfish. And while, obviously, millennials know that having a child will be harder than having a dog -- even a high-maintenance one -- they may be shocked by just how much more difficult it really is.

Let’s start with the cost. While a dog will cost you an average of $1,300 - $1,800 in the first year of its life, according to the ASPCA., a child will cost you ten times that or more. The average family will drop more than $12,000 a year on a child, according to data from the Census Bureau. “Babies require a lot more stuff — like car seats, cribs, linens, diapers, clothing, diaper genies (yes, that’s a thing), bathtubs, etc.,” explains New York-based relationship expert April Masini. “Pets require half a dozen items — like a bed, scratching post, litter box and collar — and besides their food, you’re good.”

What’s more, while you can leave your dog at home alone while you head to work or out with friends, a child is a different story. Getting a babysitter to go out for a few hours will average you more than $40, according to Care.com data. And if you need to go to your full-time job, you’re probably going to have to pony up for daycare at an average of $18,000 a year. Full-time doggy daycare comes in way cheaper, at between $2900 and $6600 a year, according to Angie’s List.

The time commitment -- and ensuing exhaustion -- is another big difference. Sure, you spend a lot of time with your dog, but you’re often chilling during that time. Parents aren’t, as children are much more “higher maintenance” Masini notes. That may be why parents say that 12% of the things they do to raise their children are “very tiring,” according to Pew.

And quite frankly, it’s much harder to parent a child than it is a pet, as M.A. Wallace notes in her NYMag.com piece “Pets Are Not Children, So Stop Calling Them That.” “In stark contrast to pets, children are always trying to outgrow, outflank, and outsmart their parents.” Meanwhile, Fido’s just happy to see you when you get home each day.