"As you know, I had been telling Eric it was probably time to get a vasectomy because I felt like we were done. But I just feel like God always has other plans," the star, 35, continued via her Instagram Story. "It was extremely shocking and surprising but [we're] happy, excited. I love being a mom. It was God's plan for me to have another ... so grateful."
"Being able to have another little baby is the most incredible blessing. We are all just over the moon," she added of their three other kids. "It's all any of us can think about."
Another fan questioned how the NFL alum, 36, reacted to the unexpected pregnancy, to which she replied, "He didn't believe me, actually."
"He thought I was playing a joke on him, because you guys know I'm such a jokester. But I would never joke about something like this," she shared. "So I think he didn't believe me until I physically peed on a stick and was like, 'I'm not joking. This is real.'"
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On the other hand, their kids — sons Forrest, 5, and Eric Jr., 7, as well as daughter Vivianne, 9 — were jumping for joy right away.
"Told them pretty fast mostly due to excitement and we are too tight to keep that secret," the Kittenish founder, who's in her second trimester, spilled. "But I also wanted them to understand why mommy was gonna so slothy and tired and not as energized as I always am."
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The idea of a vasectomy is something the couple has openly discussed with fans, but the athlete was hesitant to go through with the procedure because "he says it takes, like, his manhood away from him," the brunette beauty previously explained.