Witness Reports: Casey Anthony Used to 'Knock Out' Caylee

April 6, 2010 — -- Casey Anthony told two fellow inmates that she used to "knock out" her daughter, Caylee Anthony, so that she could go out at night without hiring a babysitter, according to documents released today by prosecutors.

Inmate Robyn Adams, with whom Anthony exchanged 50 letters while incarcerated, told investigators that Casey Anthony told her that she sometimes used "stuff" to put her daughter to sleep. Another inmate, Maya Derkovic, said Anthony told her a similar story, but never said how she "knocked out" the toddler, according to the documents released today.

Investigators suspect chloroform, a powerful sedative, could have played a role in the death of Florida 2-year-old Caylee Anthony after police say traces of the drug were found in the trunk of a car driven by Casey Anthony and in a syringe that was found near the toddler's remains.

Casey Anthony is awaiting trial on first-degree murder charges in the death of Caylee and has been in an Orange County Fla. jail since the summer of 2008. She has pleaded not guilty.

More than 250 pages of letters written between Anthony and Adams in the early months of Anthony's incarceration were released by prosecutors today, along with other documents.

The defense team for Anthony emphasized in a statement that the letters written by their client "do not contain a single reference to chloroform or any admissions of guilt.

"The letters released today reflect the natural desire for companionship when isolated for 23 hours a day, and clearly demonstrate Casey's unconditional love for her daughter Caylee," the statement said. "Casey Anthony maintains her innocence and looks forward to her day in court."

In the letters, Anthony says she thinks about her deceased daughter daily.

"I miss my Caylee so much," she wrote in one of the letters.

"Not a day goes by that I don't think about Caylee and wish that I could have protected her better," another reads.

Adams told investigators Anthony told her that there was no Zenaida Gonzalez, the babysitter Anthony originally claimed had abducted Caylee. Adams said Anthony told her that Zenaida was the first name of a childhood friend, according to the court documents.

Caylee Anthony disappeared in June of 2008 but was not reported missing until the following month. That October, Casey Anthony was charged with the girl's murder. In December, Caylee's body was found less than a mile from the Anthony home.

Adams told police that once when searchers thought they had found Caylee's remains but were mistaken, Anthony giggled "not like in an evil way...like... it's not my daughter." But once another set of remains were found near her home, Anthony became terrified, Adams said. Those remains were later identified as Caylee's.

Anthony's defense team said Adams' sole purpose in corresponding with Anthony was "to create leverage to get out of prison early."

Letters: Casey Anthony Claims Childhood Sexual Abuse

In another revelation, in the letters released today Casey Anthony writes she was sexually abused by her brother when she was younger.

"The worst part is, when I tried to confide in someone before... they turned on me. I was to blame for my own brother walking into my room at night and feeling my breasts while I slept," she wrote.

The Anthony family categorically denied such allegations.

"The Anthony family denies that there was any improper sexual behavior in their family nor was there ever a time when Casey told them of sexually inappropriate conduct by her brother or father," the family's attorney, Brad Conway, said in a statement.

Casey Anthony Jail House Letters Released

Amidst the pile of flowery, hand-written notes, Anthony repeatedly complains about what she called her family's betrayal.

Anthony said she learned that after jail house visits, her brother and father were reporting on her to the police early on in the investigation.

"I find out that my brother was acting according to scripts, via law enforcement, when he came to visit me back in July and August and he was reporting back to them with whatever I told them," she wrote.

After Anthony found out her mother Cindy Anthony had applied for a trademark for Caylee's name, she wrote in one letter, "B-E-T-R-A-Y-A-L!!! I'm so sick to my stomach even thinking about this.

"I've done everything possible to hold my family together and I continue to get stomped on, thrown under the bus, and it doesn't surprise me anymore when it happens," she wrote.

Beyond the complaints and more personal revelations, Anthony discusses boys and letters she received from admirers repeatedly asking to marry her. She talks about what's on television, often punctuating with exclamation points and smiley- or frowny-faces.

"I need a vacation!," she wrote. "I am thinking of Costa Rica... want to come with? (Unfortunately we have to wait until we are released. Someday!)"

Anthony's defense team reportedly did not object to the letters' release, telling ABC News' Orlando Fla. affiliate WFTV they are not concerned with the content of the letters.