Being a parent involves a lot of struggle and sacrifice. No matter how much you work and save to make ends meet, you sometimes need a little help.

This was the case for Krystal Preston, who is a single mom to three children. She was trying to work to support her children and take care of all their needs, but was having a lot of trouble getting it all done without a car at her disposal.

That’s when her oldest son, 13-year-old William Rabillo, had an idea to help.

William saw an ad for a 1999 white Chevy Metro on Facebook’s Marketplace and reached out to the seller about buying it. “It was really cheap so I asked if I could trade the Xbox or earn it,” William told local ABC affiliate KOLO. “At first she said no, but then she thought about it and she said yes.”

The teen then worked odd jobs, like mowing lawns and cleaning yards, to earn the rest of the money he needed.

Preston had no idea what her son was up to until he told her the news, and then she couldn’t believe it until she saw the car with her own two eyes.

“I lost it. I bawled so bad,” Preston said. “I was just like ‘There’s no way.’”

“At my low point, here comes my son,” Preston said. “Everybody goes through rough patches in life, but there’s good that can come from any situation as long as somebody with a heart does it.”

Neither Krystal nor William expected their heartwarming story to spread as a result of a viral Facebook post. “I saw people on YouTube and they get their mom a car,” William said of the inspiration behind his generosity. “I wanted to do it.”

“What 13-year-old do you know who buys their mom a car? I don’t know any,” Preston told KOLO. “I can’t express it. There are no words that can express my gratitude and how proud I am.”