Khloe Kardashian's biggest fans are nieces North West and Penelope Disick

It's safe to say Khloé Kardashian has thecutest little fans! The 31-year-old, who is fresh off releasingher new book, Strong Looks Better Naked, took to Instagram onThursday to share a photo of nieces North West and Penelope Disick holding upher memoir. While the tots might be too young to read, they certainly couldn’tlook more excited to see their aunt on the cover.

Khloé captioned the adorable picture, “I can't stopsmiling when I look at this photo! I love my little ladies!! They were soexcited and kept screaming "KoKo!" "KoKo!" North calls me"KoKo Loco."

Just this week, the Keep Up with the Kardashians starreached number four on the New York Times Best Seller List. Sharing her excitementon social media, she wrote, “Words can not explain how lucky I feel to be a NewYork Times best-selling author. Thank you to everyone who has supported methroughout my journey!”

Photo: Getty Images

Unfortunately, Khloé had to cancel a book signing onWednesday. She tweeted fans, “Dolls! So sorry Ineeded 2 re schedule my book signing. I'm sick &dr's orders are that I needto lay low until we narrow down what's wrong.” The reality star followed up with a secondtweet writing, “Ill be going for more testing today. I'm very sorry again.Stress can run our bodies down so please everyone take care of yourselves.”

We're sure her sweet nieces will cheer her up in the meantime!