Teresa Guidice's four daughters are excited about starting school, even as they continue to struggle with their mom being away, serving out the remainder of her 15-month prison sentence.

"Everybody's doing good," the "Real Housewives of New Jersey" star's 36-year-old sister-in-law Sheila Guidice told Radar Online. "They're all getting ready for school. Gia's already starting high school!"

Sheila added every weekend Gia and her sisters, Gabriella, Milania and Audriana, all visit their mom at the Danbury Correctional Facility, where she is being held in Connecticut;

"Everyone is looking forward to her arrival home," Sheila added, noting that she is slated to be released sometime around Christmas. Once Theresa is released, the girl's father Joe is slated to start serving his 41-month sentence on similar charges.

Reports are Joe has been greatly distracted as of late about the idea of soon being without his freedom, and he has even neglected his daughters as he struggles with that reality.

OK magazine reported Joe is now rarely around to spend time with or care for his four young daughters.

"Joe is a completely unfit parent," said a source, hinting that he has become so preoccupied with worrying about his own plight, little else seems to matter to him.

Both Giudice parents were convicted on bank fraud-related charges late last year, and at the time of their sentencing, the judge staggered when they would have to serve their time so that someone would always be left to care for their daughters.

"There was good reason Teresa was so worried about leaving him in charge," a source added.

Reportedly, Joe now spends most of his evenings at Rails Steakhouse in nearby Towaco, leaving Gia to be pressed into the role of "substitute mom."

Over the last several months, he's also been romantically linked to several women, though he vehemently denies being unfaithful to his wife.