Kendall Jenner rocks a bikini

Kendall Jenner, 16, showed off her beach bod as she hit the shores of Malibu on Saturday. The model rocked a turquoise bikini and shades as she tossed around the football with a friend and her nephew, sister Kourtney Kardashian's 2-year-old son Mason. Dressed in Hawaiian-print trunks, the little guy looked happy to spend some special time with his aunt! (His mom must have been at home with his new little sis, Penelope Scotland, who was born July 8.)

Later, Jenner tweeted a video of herself and a friend listening to Kanye West's song "Mercy" as they cruised back from the beach because no Kardashian family member's day is complete unless she's also promoted another family member (or boyfriend of)! Think Kim's man ever gives Kendall and co. a private performance?

Besides all her Kanye-inspired jamming, Jenner's also been busy with a new project — a book! She and sister Kylie, 14, revealed to E! last month that they're working on a young adult-novel targeting fans of Twilight, The Hunger Games, and Harry Potter. "We want to do something so different, something that we really love," Kendall told E!, adding that English is her favorite subject. The girls are working with a co-writer, author Maya Sloane, on a science-fiction story set 200 years in the future. If all goes as planned, the Jenner gals' tome will be available in time for us to pack it in our beach bag by next summer.

Would you buy a book written by the sisters?