Conrad gave birth to Liam on July 5 after announcing her pregnancy in January. She returned to the red carpet at a celebration for her Kohl's LC Lauren Conrad runway collection in Los Angeles in September.
"I took a photo of [Liam] yesterday," Conrad told People at the event.
"I looked at it next to his 1-month photo, and he just changed. Like he was a completely different baby, and I was like, 'Oh my God.'"
"I think that you can become a little overwhelmed, just being at home with your baby all day," she confessed. "But seeing how fast they change, you realize it's so important not to miss anything."
"It's been great!" the star added of motherhood. "Honestly, it's exactly as everyone describes it. It's the best and hardest thing you'll ever do."
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