Kids' credit cards, who pays?

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NEW YORK (CNNMoney.com) -- Question 1. If a child or a teen who is not 18 receives a credit card in the mail and they decide to sign and use the credit card are they responsible for the payments? Jason, Indiana

Bottom line is that if you're younger than 18, the contract between you and the credit card company is null and void and you would not be legally obligated for the balances. The bank will have to eat that amount.

That said, credit card companies know this and they won't intentionally try to send you a credit card if you're a minor. Keep in mind that just because you receive a credit card application in the mail, it doesn't mean you will receive the credit card. And if this is you, don't use the card if you're under 18.

Question 2. My son is 22 years old and his girlfriend is 24 years old. They are considering marriage. But she has awful credit. If my son marries his girlfriend, does he be affected by her poor credit? Mary, Florida

The good news is that your son won't be affected directly.

They can open a joint bank account without giving any thought to their credit scores according to Credit.com. However the couple should avoid opening up a joint credit card.

A low credit score may also become an issue if they decide to get a mortgage and buy a house.

My best advice here: wait until the girlfriend can clean up her credit score before they go applying for a mortgage.

Question 3. If you file for bankruptcy, I understand there is a 5-year payment term to your creditors, at a negotiated rate. During those 5 years, can you purchase anything, such as a new car? Rose, New Jersey

You're talking about a Chapter 13 bankruptcy.

According to bankruptcy attorney Claire Ann Resop, you cannot incur more debt until your plan is over and your case is discharged. But there are exceptions.

Let's say your car dies and you need it to get to work. You should ask your bankruptcy trustee for approval and you probably won't be denied. However you do have to show that your request is necessary and that you'll be able to make the payments.