PHOTOS & VIDEO: Amanda Knox's Appeal Trial Delayed; New Prison Letters Revealed

In December 2009, Knox was convicted of sexually assaulting and fatally stabbing her roommate, British exchange student Meredith Kercher, on November 1, 2007. She was subsequently sentenced to 26 years in jail. Two other men were also convicted in the case, including her Italian boyfriend.

Knox's attorneys claim DNA evidence in the original case needs to be reviewed for errors such as inconclusive results and contamination.

When her appeal trial begins next month, there will be six new jurors ( five women and one man)  and two new judges, president Claudio Patillo Hellmann and an assisting judge.

Prosecutors also appealed her sentence Wednesday, asking that it be changed to life in prison.

Meanwhile, new letters - written by Knox from behind bars and obtained by ABC News - show the strain of her life in prison.

Knox wrote letters to a member of the Italian parliament who has visited her in jail and has written a book about the Seattle's woman case.

In a poem included in a letter to Italian MP Rocco Girlanda, Knox writes that her life "has a rainbow running through it" and talks about a "winding road home through the wind and rain...

"I'm singing through the blues and the violet/ Until the day when I'll be home again," she writes.

In other letters to Girlanda, Knox thanks him for "the means to come alive intellectually." She tells Girlanda that he has "given me the gift of your hopes" and "shown me friendship, respect and understanding when I needed it most."

Knox ends some of her letters by quoting a line from an Italian pop song, "I know I am not alone even when I am alone."

The letters are adorned with peace signs. Next to her signature on one letter is a heart and inside the heart is a peace sign.

One note to Girlanda is written on a post card that shows Mount Hood in Oregon where Knox says she loves to go camping.

Knox's family said it was particularly difficult since it was the day before Thanksgiving.

"Every holiday is just, it's painful," Knox's mother Edda Mellas told Good Morning America Wednesday. "There's always an empty seat... The holidays are always tough."

Mellas acknowledged that her daughter was struggling with the appeal. "I know that she's obviously nervous. I mean she's facing an appeal, she's been wrongly convicted. So all of this is really hard for her," she said.

Knox's defense attorney Luciano Ghirga also said she is "dispirited and stressed."