Watt finally got to meet and hold his nephew Logan.
Watt tweeted, "Logan is so Incredibly precious and I am honored to be his favorite uncle. I intend to defend that title with every fiber of my being!"
Houston Dash star and girlfriend Kealia Ohai also held the little bundle of joy.
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Los Angeles Chargers fullback Derek Watt posted a photo of his new baby with the caption, "what better way to spend our first wedding anniversary than welcoming our son, Logan James Watt, to our family!"
It looks like J.J. and T.J. Watt can add L.J. to the bunch! Derek's middle name is John, but he doesn't go by D.J. All three brothers play in the NFL.