A Toms River babysitter convicted of shaking an infant to death in 2012 thinks her 15-year prison sentence is excessive.

A panel of appellate judges, however, rejected her appeal this month.

Fourteen-month-old Mason Hess died in August 2012 four days after Michelle Heale called 911 to report that the boy was having trouble breathing.

Heale said she believed the boy had been choking on applesauce. In an effort to help him, she said she threw him over her shoulder and patted his back. She said the boy's head seemed to snap and go limp.

Doctors who examined the child, however, found no signs of choking. An autopsy of the child's brain found injuries that suggested that the boy had been repeatedly shaken.

Heale had twins a several months older than Mason, who she was watching as a favor to his parents, who were her and her husband's neighbors and friends.

In this Tuesday, March, 17, 2015, photo, Kellie Hess, mother of victim, 14-month-old Mason Hess, testifies during the murdertrial of Michelle Heale. (AP Photo/The Star-Ledger, Patti Sapone, Pool)

A Monmouth County jury acquitted Heale of murder but convicted her of first-degree aggravated manslaughter and second-degree child endangerment.

At Heale's sentencing in 2015, Mason's father said Heale deserved to die for what she did.

She was sentenced to 15 years for the most serious offense, of which she must serve at least 85 percent before she is eligible for parole.

Heale appealed the sentencing and her convictions, arguing among, other points, "egregious prosecutorial misconduct" and that she was denied a fair trial because the victim's parents were allowed to sit too close to the jury.

Her appeal also argued that the prosecutor's closing arguments to the jury improperly referred to God when she stated, "How in God's name do you know where it happened? How in God's name ...?"

The appellate decision on Jan. 3 says the prosecutor "did not overstep the bounds of a fair closing argument," and that the judges found no improper conduct by the victim's parents or any evidence that Heale did not receive a fair trial or that the judge did not hand down a reasonable sentence.

The earliest that Heale can be let out of prison is Jan. 15, 2028.

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