Alongside a video of flowers and leaves blowing in the wind, Hilaria wrote, "Today was your due date and we wanted to meet you so much."
"I have been afraid of this day to come -- but it is here and I will be brave," she continued. "You were so loved and you always will be. I think of you every day and I wish so much that our path had been different."
"Mommy loves you, my sweet girl," Hilaria added in the note to her unborn child.
ET's Rachel Smith spoke to Hilaria and Alec shortly after she suffered the miscarriage, and they revealed that they still wanted to try for more kids. The couple, who are parents to Carmen, 6, Rafael, 4, Leonardo, 3, and Romeo, 1, is currently expecting their fifth child.
"If you have kids, and if you're like us, sometimes you feel like you can't stop having kids," Alec said at the time. "Every time we have them, we're like, 'This is great. Let's have more!'"
"We can't end on that note. I don't want to," Hilaria said. "At least, we're trying not to end on that note. Cause that was a sad note."
"Yeah, we're gonna have another one," Alec agreed. "We're gonna have another one."