This morning, he posted this photo on Facebook and Twitter wishing a happy 98th birthday to his great-grandmother. The photo quickly went viral, getting more than 100,000 likes in just half an hour.
It's not the first time the Houston Texans defensive end has shared a moment with his great-grandmother. Back in 2012, he shared this photo on Twitter where he gave her and his grandmother an on-field tour at NRG Stadium.
Watt's been having a heart-warming week for his fans. Just yesterday, he visited 11-year-old Manuel Jimenez in the hospital. The young boy is recovering after being wounded in a drive-by shooting that killed his 6-year-old brother, Moises.
PHOTOS: Houston Texan's J.J. Watt