Hilary Duff: Son's Belly Button in Makeup Drawer!

Hilary Duff gets her caffeine fix at the Coffee Bean & Tea Leaf on Friday morning (April 20) in Toluca Lake, Calif.

PHOTOS: Check out the latest pics of Hilary Duff

The 24-year-old new mom recently shared a big day in her 4-week-old son Luca‘s life.

“You know what was a big milestone?” she told People. “The belly button falling off. That was a huge one. And then I wanted to keep it but my husband was like, ‘No, that’s gross, you can’t keep it!’ I’m like, ‘I’m totally keeping it,’ and I secretly kept it.”

“But now it’s not a secret anymore,” Hilary laughed. “It’s in a Ziploc bag in the back of my makeup drawer. Luca‘s going to think I’m a freak!”

15+ pictures inside of Hilary Duff at Coffee Bean…