AceShowbiz -

Kendall Jenner and Jordan Clarkson have kept fueling dating rumors. The "Keeping Up with the Kardashians" star and the basketball player were spotted together in and around L.A. during the Fourth of July weekend.

An insider tells PEOPLE that Kendall and Jordan's relationship is "getting stronger." "They're both more private," the insider shares, "When they're out in public, they are never all over each other." While the couple kept any PDA to a minimum while celebrating Fourth of July at Bootsy Bellows' "Red, White and Bootsy" party, their "relationship has been getting stronger over the last couple of months."

"They're very openly affectionate when they're comfortable ... with friends or alone on a date," adds the insider, "They enjoy low-key dates like quiet dinners where they won't be bothered."

While another source previously told the site that Kendall and Jordan's relationship wasn't completely "serious" yet, the insider claims that the couple is definitely heating up. "They really like each other and Jordan is super into Kendall," says the insider.

Kendall first sparked dating rumors with Jordan back in March. At the time, the 20-year-old reality star and the 23-year-old basketball player were spotted together at The Nice Guy in West Hollywood after his team beat the Miami Heat by two points.