Brittany and Patrick Mahomes released joint Instagram reels Friday announcing that they are expecting their third child. Brittany and her Kansas City Chiefs quarterback husband are already parents to daughter Sterling Skye, 3, and son Patrick Lavon Mahomes III, 18 months, and the whole gang participated in the adorable pregnancy reveal. The couple shared a video that showcased each member of the family dressed in off-white outfits. The kids were giggling and bouncing about, while their very famous parents interacted lovingly with them, at one point holding hands and dancing. Sterling raced rig…