Christopher Vaughn dropped more than $4,700 in two visits to a topless dance club just days before he allegedly killed his wife and three children.

Receipts from Scores Chicago presented during the Oswego man's murder trial Thursday show that Vaughn was there on the nights of June 5 and 11, 2007, spending thousands of dollars to buy alcohol and spend time in a private room with a dancer named Cassidy.

The expenditures were quickly discovered after the June 14, 2007, deaths of his wife Kimberly and children, Abigayle, 12, Cassandra, 11, and Blake, 8, because Vaughn not only used his credit card to cover the bill but let the club to make copies of his driver's license and thumb print to ensure payment.

By June 27, 2007, Cassidy -- whose real name is Chrystal Miller -- was testifying before a Will County grand jury about her experiences with Vaughn.

She was asked to do so again Thursday, but her memories were quite a bit more "vague," she said. One thing that stayed with her, though, was his introverted demeanor, she said.

"He was very timid, very shy and uncomfortable," said Miller, who's no longer an "entertainer" at the club near Chicago's O'Hare Airport.

In her grand jury testimony, portions of which were read aloud to her for possible verification, Miller was more specific in her recollections.

Among them, Vaughn told her one evening that he'd been single for five years and had no children. He also accompanied her a private room, she testified, but didn't ask her to do a "lap dance," as most men request given that they've paid an extra fee to be alone with a dancer and have to make a minimum drink purchase of $200 to $300.

"He was such a gentleman, such a gentleman," Miller told the grand jury. "He didn't make me dance or anything."

Miller did recall what she considered to be a "strange" reference about the "future" that Vaughn made when he was getting ready to leave after his second club visit, she said Thursday.

While she could not remember it specifically, her grand testimony was read aloud to her for her verification. She recounted it this way:

Miller: "I hope to see you in the future."

Vaughn: "Do you know what's going to happen in the future?"

Miller: "Well, no, do you know what's going to happen in the future?"

Vaughn: "I do."

In other testimony Thursday, Mark Daniels, owner of Mega Sports in Plainfield, confirmed Vaughn made two visits to the retail gun store to use its shooting range, the first on June 6, 2007, and the other on June 13, 2007, the day before the murders.

In both cases, Vaughn presented his firearms owner's identification card and put his name down on a signup sheet to use one of the shooting lanes, Daniels said. Videos show Vaughn entering and exiting the store and using gun range, the second time dressed in a long-sleeved jacket despite it being mid-June.

The jury was also read a series of email notes written by Kimberly Vaughn to University of Phoenix classmates with whom she was working on online criminal justice class assignments. In many, she made references to enjoying the classwork and to her husband, with whom she planned to one day start a private investigation firm, she wrote.

She also shared information about their relationship and how they'd successfully "blended" their likes, went out on "date nights" and attempted to accommodate each other, such as her learning to like to eat fish because her husband was an outdoorsman who liked to hunt and fish.

In one, she wrote that her older sister and her husband were her "heroes," saying "I admire what they've done and what they've accomplished in their lives."

Here are the stories from the previous days of testimony:

Vaughn Worried about Boots, Jacket, but Not Wife and Kids, Witnesses Say

Kimberly Vaughn 'Happy' in Days Before Murder, Witnesses Testify

Grim Death Scene Photos Don't Rattle Chris Vaughn on Murder Trial's First Day

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