TAMPA, Florida — A suburban Florida soccer mom showed signs of trouble in the months before she was accused of killing her two teenage children: Her 16-year-old daughter told police in November she had been hit by her mother, and troopers investigating a car crash thought the woman had been using drugs.

The incidents were described in reports released Monday, several days after authorities say Julie Powers Schenecker, 50, shot and killed the kids because they were talking back and being "mouthy."

Story: Mom charged in teens' slayings out of hospital

Investigators found her soaked in blood Friday on the back porch of the family's upscale home. Later that day, at a county jail, Schenecker shook uncontrollably, her eyes wide.

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Investigators said 16-year-old Calyx and 13-year-old Beau had each been shot twice in the head a day earlier — Beau in the family's car on the way to soccer practice, Calyx in her room as she studied at her computer

Both teens were killed with a .38-caliber pistol, which authorities say Schenecker bought five days earlier.

Schenecker was ordered held without bail Monday during a brief court hearing. She did not speak — though she did cry and hold a tissue, her hands bound by handcuffs.

Neither Schenecker nor her husband, Parker — an Army intelligence officer who was working in the Middle East when the shootings happened — had a criminal record.

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Parker Schenecker served in Munich from 1986 to 1990; his wife worked there from 1987 to 1992 as a Russian linguist involved in military intelligence, wrote an author identifying himself as Parker Schenecker on an online forum for military personnel.

The family moved to Tampa in 2008 when Parker Schenecker was transferred to U.S. Central Command headquarters, which oversees the Iraq and Afghanistan wars and is housed at MacDill Air Force Base.

Video: Police: Mom planned kids' murders

Friends and neighbors recalled a perfect family, whose Facebook photos showed a radiant foursome posing in Santa hats and decked in white near a pier.

On Nov. 6, though, trouble arose.

Calyx called police, telling officers her mother hit her as she drove home in the family car, according to a Department of Children and Families report. The teen also told officers that her mom had hit her about a month and a half before.

Two days later, Schenecker was in a car crash not far from her Tampa home. Officers on the scene wrote that Schenecker "showed signs of drug impairment," including dilated pupils with no reaction to light and "mush-mouthed speech."

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