An autopsy found that the body of Kamille "Cupcake" McKinney, the 3-year-old Alabama girl who was found dead in a dumpster after she was kidnapped from a birthday party, was given methamphetamine and a sedative before she was murdered, according to reports.

Prosecutors stated Tuesday during a preliminary hearing for Patrick Stallworth, 39, that he and his girlfriend, Derick Brown, 29, used candy to lure Kamille away from the birthday party on Oct. 12 and kidnap her, ABC Birmingham affiliate WBMA reported.

Birmingham Police detective Jonathan Ross testified that he spoke to a 10-year-old at the birthday party who said he saw a man and woman in an SUV handing out candy and that he saw Kamille in the SUV crying, according to WBMA.

A middle school-aged girl also told Ross that earlier in the day the couple had offered her candy while she was leaving her cheerleading practice, he said at the hearing.

Surveillance video from a nearby gas station allegedly shows Stallworth getting out of an SUV and buying $18 worth of candy, Ross testified. Stallworth allegedly later bought an energy drink and a pill for sexual dysfunction at another gas station, Ross reportedly said.

After he was identified, Stallworth allegedly admitted to coming in contact with the cheerleader and handing out candy to children in the vicinity of the birthday party, but he did not mention anything about Kamille, Ross reportedly said.

Investigators also allegedly found child pornography on Stallworth's cellphone, Ross testified. The dumpster where Kamille's body was later found was located near Stallworth's apartment complex, Ross reportedly said.

After Stallworth was arrested, he allegedly told Ross that he first saw Kamille with Brown when he arrived home to their apartment and that the two were sitting on the sofa and watching television.

According to WBMA, Ross testified that Stallworth said Brown wanted to "keep her" and then instructed him to sexually assault her. Stallworth then went outside to smoke a cigarette and accused Brown of putting her hand over Kamille's nose and mouth to kill her, Ross said.

Ross believes that the couple gave Kamille meth and another sedative to make her sleepy, according to the WBMA's report of the hearing. The sedative that was allegedly used, Trazodone, is an anti-depressant used to treat insomnia, and the levels of both drugs in Kamille's system indicated that she ingested them and was not just exposed to them, AL.com reported.

Kamille's family was in the courtroom during the hearing, according to AL.com.

The medical examiner ruled Kamille's cause of death as asphyxiation, prosecutors revealed in the couple's Oct. 25 arraignment hearing. Prosecutors said during Tuesday's hearing that they couldn't determine whether sexual abuse happened due to decomposition of her body, according to WMBA. Ross reportedly testified that a plastic mattress cover found in the apartment had a blood stain and DNA from Stallworth, Brown and Kamille.

Stallworth and Brown are both charged with capital murder of a victim less than 14 years old. Brown is expected to appear in court on Friday.

Stallworth's defense attorneys argued during court that the witness accounts were inconsistent and Stallworth was not with Brown for a portion of the day of the birthday party, according to WBMA. The attorney also said that the reason why Stallworth's phone pinged to the area is because Brown had it with her in the SUV, since hers was broken.

A judge ruled Tuesday that there was enough evidence to send the case against Stallworth to a grand jury, The Associated Press reported.

Stallworth's attorney, Derrick Collins, declined to offer a statement to ABC News, citing a court-ordered gag order.

The Jefferson County District Attorney's office and a public defender for Brown did not immediately respond to ABC News' request for comment.

ABC News' Emily Shapiro contributed to this report.

