Lauren Conrad feels "overwhelmed" being a mother.

The 31-year-old reality star welcomed her first child Liam James - who she has with her husband William Tell - into the world on July 5 this year, and the 'The Hills' alumni has admitted spending everyday at home with her new-born needed some getting used to, but giving birth is the "best and hardest thing" she has ever done in her life.

Speaking to PEOPLE, the blonde beauty said: "I think that you can become a little overwhelmed, just being at home with your baby all day.

"Honestly, it's exactly as everyone describes it. It's the best and hardest thing you'll ever do.

"It's amazing. You fall so in love with your tiny person -- it's a whole new life."

And the 'Laguna Beach' star takes a photograph of her tiny tot every month so she can compare each image with one another to monitor her child's progression because she doesn't want to "miss anything".

She explained: "I took a photo of [Liam] yesterday. I'm trying to take a monthly photo -- all of the good moms do it -- I'm really trying. So I took it and I looked at it next to his one-month photo, and he had just changed. Like he was a completely different baby, and I was like, 'Oh my God.'

"But seeing how fast they change, you realize it's so important not to miss anything."

Lauren has revealed comparing the difference in Liam as he grows up makes it "harder" for her to ever leave his side.

She added: "It almost makes it harder to leave them."

The style icon has also hailed her 37-year-old spouse as a "great" father, and has revealed he is "not afraid" of young children as he is used to being around babies, more so than Lauren.

She said: "He's great. He's not afraid of babies, which is really helpful. He was 11 when his younger sister was born, so he has a lot of experience with babies. So that was really nice. He had way more experience than I did."