Standing on a football field and wearing Webb's number 18 jersey, she pointed to the sky. From behind, loved ones then doused Kay in blue Gatorade, revealing that the baby will be a boy. She later released a bunch of blue balloons off into the sky.
"I know you picked him out to protect me. He's gonna be a legend just like his daddy. I love you both forever @spider_ #babyspidey," Kay wrote in the caption.
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The model shared the pregnancy news last month on Instagram with a photo of herself holding a sign with the baby's sonogram and the words: "Coming soon: Baby Webb."
"We created an angel before heaven gained one," she captioned the post. "All you ever wanted was to be a father…I know you'll be the best one from up above."
"Can't believe I have to do it without you but knowing I'll have a piece of you keeps me going," she continued. "I can't wait to meet the person that's half you, half me. I love you forever, both of you @spider_."
Kay also remembered her late boyfriend on Instagram following the accident, calling him her "best friend" and "twin flame," adding: "I've never loved anything as much as I love you."
getty; kelly kay/instagram
The standout tight end for the Ducks died in July when he fell and hit his head near Triangle Lake, about 35 miles from the University of Oregon's Eugene campus. Oregon's head coach Dan Lanning confirmed Webb's death on Twitter.
"So full of life in every moment of the day. Your smile and energy will be missed Spencer. I love you!" Lanning wrote at the time.