Image: Two young women putting shopping bags in car © Dan Dalton, Digital Vision, Getty Images

Every parent is probably guilty of giving in to his or her kids when it comes to spending money.

Whether it's buying a candy bar at the checkout counter or sending a well-timed check to cover the wedding caterer, spending money to make kids happy is a natural impulse, says Leisa Brown Aiken, a certified financial planner in Chicago.

"Parents want their kids to be happy," Aiken says. "And they're really good making you feel like if they don't get it, they're going to be unhappy and you're a terrible parent."

But giving in to those impulses can have serious financial consequences, says Joan Koonce, a professor and financial planning specialist at the University of Georgia.

"Parents are trying to provide (kids) with these things, and sometimes it's a bad situation because they really can't afford it," she says.

Worse,it creates a pattern that repeats itself as children get older, with ever-higher stakes for both parents and their kids. "When they leave their parents' household for the first time, many of them end up in a lot of debt," Koonce says.

Here are some dumb financial moves that children commonly demand and how to push back:

Buying expensive brands over cheap alternatives

Brands and the powerful advertising that pushes them exert a strong influence on kids. The U.S. food industry alone spends billions of dollars a year advertising to children.

And because children are naturally much less critical consumers, that advertising can be effective. Among children 2 to 6 years old, just a 10- to 30-second exposure to advertising can influence food, drink and toy preferences, according to a Stanford University study conducted in 2001 and still quoted in textbooks.

Taken in by advertising, kids will push to spend money on expensive brands, a phenomenon so common scientists have dubbed it: "the nag factor."

"The $1.50 yogurt versus the $4 yogurt isn't the biggest problem. The problem is you've set that pattern, and then when it's middle school, your kid only wants $75 T-shirts," Aiken says. "If your kid was buying $20 or $15 T-shirts, the rest of that could be going in your college fund."

How to say "no": For young kids, a fun way to demonstrate that cheaper brands and name brands are often similar is a blind taste test. Ask kids to identify which is the brand name and which is the generic. Even if they're correct in identifying the products, they'll still notice how similar the flavors are.

Keeping up with the Joneses

Kids face peer pressure, and that pressure sometimes translates into persistent demands to spend money on the same kinds of electronics, clothes and even cars that their peers' parents buy, even at the expense of the family's long-term financial well-being, Aiken says.

"They're in school or they're bombarded with all these marketing messages, and they don't have experience, they don't have the long view. They're kids. The long term to a 6-year-old is 15 minutes," she says.

While you may be able to afford to give in to the pressure now, keeping up with the Joneses leads kids to expect a standard of living they may not be able to maintain later in life, Aiken says.

How to say "no": When a child brings up what he or she has seen peers getting, break out your own financial plan. Explain your goals for retirement savings and other things you value more than keeping up appearances, says Laura Scharr, a principal at Ascend Financial Planning in Columbia, S.C.

If that doesn't work, "You start then and say, 'Well, that's kind of a special thing that you want, so why don't you pay for it out of your allowance?'" Scharr says. "If they really do want it, they'll pay for it."

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