As parents, we're trained to save for certain expenses -- child care and college, to name just a couple. But there may come a point when your child decides to get married, and when that happens, you can't discount the possibility of being asked to help pay for that wedding. In fact, parents contribute $19,000 on average to their children's nuptials, according to data from student-loan website Comet, with $12,000 coming from the bride's side and $7,000 from the groom's.

There's nothing wrong with helping your child fund that big day, especially when even budget weddings today can get expensive. On the other hand, if you don't plan for that expense, you may be forced to rack up debt or compromise other goals, like retirement, to come up with that money.

Older man standing next to bride

Image source: Getty Images.

Save now, celebrate later

Without a crystal ball, it's pretty much impossible to predict when your child will get married. But if you start saving for that milestone when your child is relatively young, you stand to accumulate a nice chunk of cash by the day of the wedding, whenever that happens to be.

Imagine you decide to set funds aside for the wedding when your child is a year old. Sure, the idea of your baby getting married might seem laughable when you're elbow-deep in dirty diapers, but watch what happens when you commit to saving for that wedding ahead of time:

Monthly Savings Amount

Total Accumulated Over 20 Years
(Assumes a 2% Average Annual Return)

$25

$7,300

$50

$14,600

$100

$29,100

$150

$43,700

As you can see, you don't need to part with a ton of money each month to accumulate some nice cash over a 20-year period. Setting aside a mere $25 a month, for example, would leave enough money to match the average wedding contribution on the groom's side today, while saving $50 a month would leave you with well more than enough to keep up with the average bride's parental contribution. Furthermore, the 2% in the table above assumes that you're mostly sticking that money into the bank -- perhaps into a certificate of deposit. If you were to invest your cash more aggressively, you could easily grow it even more.

The longer you wait to start saving for that wedding, however, the more likely you are to scramble on the spot. And that puts you at risk of racking up debt in an effort to spare your child from that very fate.

Another problem with not saving for your child's wedding in advance? You might be tempted to pull that cash from a source you shouldn't be tapping, like a retirement plan. And even if you're at an age where you won't incur early withdrawal penalties for going that route (meaning, you're at least 59 1/2), you'll be putting your golden years in jeopardy by withdrawing funds meant for retirement.

While saving to help pay for a child's wedding should by no means trump other goals, like college or your own retirement, know that if you set aside funds early for that purpose, you'll be in a great position to help pay for that expense whenever it arises. And in doing so, you'll give your child an incredible gift: a day to remember without the crippling debt so many newlyweds walk away with.

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