Jon Gosselin knows how to throw a dinner party.
According to People, the "Jon & Kate Plus 8" star stepped out in the Hamptons on Wednesday night with "Real Housewives Of New York City" star Jill Zarin and her husband, Bobby; celebrity dad Michael Lohan, who is hosting Jon on his Hamptons trip; Jon's latest ladyfriend, tabloid reporter Kate Major; and Mark Epley, mayor of Southhampton, and his wife, Marianne.
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And Jill told the mag that Jon and his new Kate are "definitely dating" – even as Jon's People cover story with his previous – and perhaps short-lived – new girlfriend, 22-year-old Hailey Glassman, remains on newsstands.
"He didn't seem smitten. They weren't all over each other. But they're definitely dating," Jill said. "It came up in conversation. She had her hands on him. But she's young. This is a girl who is going to want to have babies. Does he really want to go out with another young girl and have kids?"
Despite her doubts, Jill said, "He seems like a great dad."
For her part, Hailey told the mag in a separate interview that his connection with Kate Major was "news to me."
"I still love Jon and Jon loves me," she said, reportedly in tears.
And for Jon, the strain of his new jet-setting single life, which found him flying to France with Hailey last week to share champagne on a yacht with Ed Hardy designer Christian Audigier, might be getting to him.
"I miss my kids," Jon told the mag.
Michael, who met Jon via his fiance's friendship with Major, said the famous dad's not neglecting his big brood.
"He talks about them. He's on the phone with them all the time," Michael told People. "But unfortunately, as I well know, being a father in a divorce, it's really hard on the kids. And you just want to be with them all the time. But some times our exes don't make it that easy."
In a separate interview with ABC News, Michael said that he'd opened his home to the paparazzi-pursued star.
"There's so much media bothering them in New York City and Pennsylvania, they needed a place to get away, and I offered them my house," Michael said. "He's a really nice guy."
Meanwhile, Kate Gosselin remains on top of her mom duties. She was spotted on Tuesday with three of the estranged couple's eight children heading to the Pediatrics Center in Reading, Penn. for some shots.
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