Losing a child is an unthinkable tragedy, and of course parents want to protect their children in every way. As a result, many insurance companies offer life insurance policies for children. But before you follow your heart and buy that policy, think about it with your head.

Jeff Opdyke, author of "The Wall Street Journal Complete Personal Finance Guidebook," writes that, in general, children do not need life insurance. Life insurance is for those individuals whose sudden loss of income due to death would debilitate their dependents financially. Since children typically don't have either income or dependents, life insurance policies for them are usually not necessary.

Parents should, however, purchase life insurance policies for themselves so that their children are protected.

There are a few exceptions. Funeral arrangements can cost thousands of dollars, and if you don't have the money to cover that expense, life insurance can be useful. Consider buying a small term policy just to cover burial and funeral expenses.

Opdyke adds that buying insurance for a child "ensures the child's insurability later on in life." If, for example, your child develops a long-term illness such as diabetes, getting her insured will be difficult. But if your child already has coverage, you can retain the policy (though your costs will likely increase).

To really safeguard your children's future, invest in a college fund and make sure that the parents are insured.