Is Kendall Jenner getting serious with rumored flame Blake Griffin? Is Kylie Jenner currently carrying Travis Scott's child? Of this, we are not totally sure, but thanks to People, we do know that the sisters spent Sunday night taking in the scary sights at Universal Studios Halloween Horror Nights in Hollywood alongside their respected fellows.

"Kylie and Kendall were both extremely loving and cuddly with their boyfriends," an onlooker told People. "Both couples had their arms around each other, and the girls were really sweet with their guys. Travis and Kylie were especially cute and lovey-dovey. Kendall and Blake had a blast going through the mazes together."

A surprisingly romantic moment for a theme park date that involves frights and gears.

The onlooker also shared that Jenner pals Jordyn Woods and Hailey Baldwin served as the double dates' fifth and sixth wheels. And although Kylie, who kept the state of any possible baby bump a mystery with a "big hoodie and leggings," wasn't able to go on every ride due to that pregnancy situation, she "made sure Travis went ahead and had fun," according to the source.

Kendall was first spotted spending time with Los Angeles Clippers player Griffin in August. Earlier this month, a source told People that things were starting to heat up between the two, who were originally reported to be keeping it casual. "She thinks he's dorky and funny, but also cool and sexy—he has a certain attractive 'swagger,'" the source said. "They are seeing each other more, and Blake is doing everything in his power to make Kendall his girlfriend."

The insider added, "She's always working and traveling and knows a full-blown relationship isn't necessarily the best idea, but things are heating up. She is for sure enjoying dating him."

Meanwhile, Kylie and Scott have been hanging out since April, when they attended Coachella together. Not long after, they both posted photos on their respective Snapchat accounts of matching tiny butterfly tattoos on their ankles, and in August, the rapper gave Kylie a $60,000 28-carat diamond-encrusted butterfly necklace for her birthday.

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