Boats, butts, and bikinis - how else would teen kween Kylie Jenner celebrate her 19th birthday? Joined by her sister Kendall (and a few other famous friends), the youngest Jenner took to Turks and Caicos for her highly-documented celebration and man, was it #SquadGoals at its best. Bella Hadid, Hailey Baldwin, and Justine Skye frolicked on the beach and in the crystal blue waters, taking selfies, Snapchats, and booty pics enough to hold us over until their next friendscation. Click through for an inside look!