A person putting money in a purse(Courtesy of Parenting.com)

They're also among the most dangerous, because when you quarrel with your partner over the kids and money, you risk not only damaging your relationship but also giving your children some very misguided notions about family finance. "Even very little kids who don't know exactly what's being said can sense tension and anger when their parents argue," says financial educator Ruth Hayden, author of For Richer, Not Poorer: The Money Book for Couples. "What they learn is that money makes Mommy and Daddy unhappy."

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Here, reasons for the most common money arguments, and how to defuse them.

Overspending on the Kids
"You spent what on WHAT?!?" "Just how many toys does one kid need?" "How much did that outfit cost?"
Bickering about overspending often comes in a familiar form: The parent primarily responsible for the child's everyday expenses --clothes, food, toys, and the occasional gift for a playmate's birthday party --is periodically taken to task by the other for overspending on necessities and otherwise frittering away money.

To stop the cycle, you have to figure out why the two of you are at such odds. One reason the parent who doesn't usually pay may react so critically is because he's genuinely clueless about how much kids' stuff really costs. To close the knowledge gap, take a few shopping trips together. "Whoever hasn't been doing the spending is often shocked and humbled by the experience," says Hayden.

Then comes the hard part: You have to sit down together and work out how much money you think is reasonable to pay for the children's clothes, toys, and activities. The key is to recognize that each of you has valid reasons for wanting to spend or limit spending, and to resist the impulse to simply label your spouse a congenital tightwad or spendthrift. Come to the discussion prepared to be flexible; showing that you're willing to change your ways may motivate (or shame) your partner into making a similar effort. "One parent is likely to end up spending significantly more than he's completely comfortable with, and one parent will spend significantly less," says Hayden. "But both should be able to walk away from the table saying, 'I can live with that.'"

Rules That Conflict
You believe your child should get a regular allowance, no strings attached, so she learns how to manage money. Your partner thinks kids should earn every penny. You allow your child to pick a treat when you shop together to teach him about making choices (and to stave off tantrums). "You're spoiling him," growls your partner.

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Recognize first that it's natural to approach teaching your children about money differently, since you didn't grow up with the same values, expectations, and rules. What's not okay is to impose your financial policies unilaterally, or, worst of all, overrule your spouse in front of your child. Not only is the lack of respect for your partner's views belittling, but you'll inadvertently teach your child to play one parent against the other.