Kourtney Kardashian debuts baby Penelope

(CBS News) Kourtney Kardashian debuts her newborn daughter in this week's issue of Us Weekly.

The 33-year-old Kardashian sister is seen on the magazine cover with her daughter, Penelope, and big brother Mason.

"Nothing could prepare me for how hard I fell in love with her," Kardashian said.

Kardashian and her longtime beau, Scott Disick, welcomed Penelope Scotland Disick on July 8, in Los Angeles.

She also posted a note on Twitter with a link to the Us Weekly cover image:

The new Us Weekly issue hits newsstands this week.