Wearing a pink and black string bikini, the 15-year-old "Keeping Up With the Kardashians" star hung out on the home's balcony with her 14-year-old actor beau, donning a black tank top. Later, the teen was seen playing in the water while Smith looked on.
Shortly after the family party -- where mom Kris Jenner, sister Kendall Jenner and their friends also hung out, Kylie tweeted about the fun she had: "Amazing fourth. Couldn't be more thankful for the people around me x."
Although she was spotted grabbing frozen yogurt with Smith's pal, Lil Twist, on Wednesday, July 3 -- fueling rumors that she had ended things with Smith -- the teen model denied she was anything more than friends with the 20-year-old rapper on her Twitter page.
"Media always making it seem like I'm dating everyone I'm seen with," she tweeted. "Makes no sense to me. Don't listen to everything u see, people."
In March, Us Weekly exclusively confirmed that Smith and Jenner were indeed dating.
"They're dating," a source said. "It's new, but they've been friends forever."
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