"There's a magic, there's just a gratefulness that you can't explain," she tells PEOPLE
Each product we feature has been independently selected and reviewed by our editorial team. If you make a purchase using the links included, we may earn commission.

Molly Sims is in love with her life.

Although the new mama admits the late nights, which include getting up every few hours to breastfeed, are “exhausting,” there is nothing sweeter than seeing her two children, daughter Scarlett May, 7 weeks, and son Brooks Alan, 3 next month, together.

“I think there’s a content you’ve never felt in your entire life. There’s a magic, there’s just a gratefulness that you can’t explain,” the model told PEOPLE at the 2015 Communities in Schools of Los Angeles Annual Gala on Monday.

“It’s so fun and I feel like my family is so important to me and lovely. There’s a fulfillness that she’s magic and she’s our magic. She has brought so much joy and fun and she’s opening up to the world and it’s awesome.”

Molly Sims motherhood happiness

Charley Gallay/Getty

Sims, 41, continues, “She was a little bit difficult to get and I got her and I’m so happy.”

And any anxiety Sims had over the bond between her kids has been washed away: The proud mama is amazed at the way Brooks blossomed in his new big brother role.

“He’s so good. He calls her baby sister, baby sister Scarlett. But he’s awesome,” she shares. “I was a little nervous, I’m not going to lie … but he’s amazing and it’s so fun, so good.”

The Everyday Supermodel author recently returned to work and while being away from her babies can be hard, Sims cherishes all her time spent with her family.

“I was like, ‘Okay, Mama is going to go for her first day of work,’ and all of a sudden [Scarlett] gave me a grin,” she shares.

“I was like, ‘Oh my God!’ I called my husband and was like, ‘She smiled!’ It was the first smile.”

— Anya Leon with reporting by Mariah Haas