Jon and Kate Gosselin spent time together with their children for a July 4th celebration at their Pennsylvania compound -- and broke the law in the process.

An eyewitness tells Life & Style that Jon lit sparklers, rockets, cherry bombs and firecrackers from his front lawn in broad daylight. "Things got so loud," says the witness, "that one ka-boom in particular sent all the kids scurrying back to the house." That prompted Kate to screech out, "Jon, I think that's illegal in Pennsylvania!"

Asked to comment, officer Thomas Deiterich of the Lower Heidelberg, Pa., police department tells Life & Style, "Fireworks are illegal for personal home use in the state of Pennsylvania." Deiterich went on to say that the law isn't usually enforced.

Although Jon and Kate kept their distance at times during the get-together, they and the children appeared to be a unified family at least for the day, according to the onlooker. "They were having fun."

Photo Credit: Courtesy of TLC