"If you ever, for a second, worry about 'goodness' in the world," she wrote in part in the caption. "If you ever think professional athletes don't connect with people...Watch this."
“People are so, so, good. And I know my cousin is beaming from Heaven,” Harb concluded.
Footage shows the boys in disbelief as they opened the door to see Matthew and Kelly Stafford. AndtThe couple didn’t come empty handed, either, as they had a huge gift bag by their side.
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The Pro Bowl quarterback stuck around to play video games with the boys. Matthew Stafford even played Madden NFL as himself.
The viral video follows what's been a tough year for the Staffords, too. In April, Kelly Stafford underwent a 12-hour brain tumor surgery. After her release following the removal of the non-cancerous growth, the mother of three daughters suffered a setback.
While Kelly Stafford continues her recovery, her husband was placed on the injured reserve list, Yahoo Sports reported. The 31-year-old has been dealing with fractured bones in his back.