While Teresa Giudice has been keeping her chin up while serving time in prison, the "Real Housewives of New Jersey" star's husband Joe Giudice says she's having a hard time with life behind bars.

"She's holding up. I can't say she's doing great but she looks good," Joe recently said during a candid interview with ET's Jennifer Peros. "She keeps her spirits up and tries to make us feel like she's OK but she's really not. She wants to be home."

Teresa's been serving time for fraud in a Connecticut prison since January and is set to be released in December. After Teresa's exit from prison, Joe is to begin his 41-month prison sentence. The couple took a plea that would allow them to serve time separately so that one of them would be able to care for their children.

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So what has Teresa been doing to pass the time in the big house?

"She's keeping herself busy," Joe said. "Just working out. What else is she gonna do in there? Read. Working out. Eat. Email."

According to Joe, his wife also has a job behind bars, although the reality star admits he doesn't know what his wife's job actually is.

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"She doesn't tell me about her job," Joe explained. "She says she's got an easy job, she likes it, she doesn't wanna change, I think she wipes down a couple tables a day. She's done within three minutes and [that's] her job. I think she's making a dollar a day or maybe a dollar a month, I'm not sure."

While Teresa's been working to keep her spirits raised, Joe says the time has been very difficult on their four young daughters -- Gia, Gabriella, Milania, and Audriana -- who visit as often as possible.

"Whenever we get there, Milania is just like, 'Mommy why can't you just come home? Why don't you just get up and leave?' and Teresa is like, 'Soon baby soon,'" Joe shared. "Adriana doesn't really say much about it but she cries sometimes."

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"In the beginning, she used to cry and now she's getting kinda used to it so now she just goes, does her thing, plays with the other kids, and then we just go home and she's happy about saying goodbye but I'm sure it's killing my wife when we all leave," Joe added.

To hear more from Joe, tune in tonight for his complete interview on ET. The three-part special following Joe and his family on "The Real Housewives of New Jersey: Teresa Checks In" premieres Sunday, Oct. 11 on Bravo.