22-year-old Megan Martzen is charged with murder and child abuse leading to the death of seventeen month old Ella VanLeeuwen back in 2009.
Martzen testified she did everything she could to bring the unresponsive toddler back, things like splash water on her face, lightly shake her and scream "wake up."
But detectives believe the little girl died from shaken baby impact.
22-year-old Reedley resident Megan Martzen cried in court as the defense played back a frantic 9-1-1 phone call she made on the afternoon of February 21st, 2009.
That's the day she claimed 17-month-old Ella VanLeeuwen fell backwards off a bed and hit her head.
"She's never wavered there was a fall off the bed of Ella and she was immediately non-responsive," defense attorney Jeff Hammershmidt said.
Our cameras weren't allowed inside the courtroom but shortly after Martzen took the stand for the first time.
During her testimony she told the jury she's an experienced babysitter having completed special training during high school.
She also worked as a teacher's aide and taught English to young children at a local church.
She said when Ella's mother dropped the toddler off earlier that day she told her Ella had fallen from her booster seat the day before and the defense claims it was multiple injuries that eventually lead to her death.
"In fact the expert that was retained from the Fresno Co. District Attorney's office has testified under oath that he believes it's an accident and that it's uncanny, that's his word, how the injuries from a booster seat fall and what Megan said happened at her home match completely," Hammershmidt said.
But Megan didn't tell this to the detective in the taped interview, and witnesses who were with Ella the day before say they never saw her fall from a booster seat.
The prosecution now has a chance to cross-examine Martzen and it will be up to the jury to decide whether the babysitter was a credible witness.