A little boy who plunged to his death from an open window in his 17th-floor Kansas City apartment left his chocolate handprints on the windowsill and down the side of the building as he fell, prosecutors have revealed.

Now, 5-year-old Grayson O’Connor’s mom, Corrinne, is going to Missouri prison for 10 years.

Corrinne did not call 911 after her son fell from the window on Nov. 27, 2023, and had removed a safety latch on the window before she opened it, prosecutors said at her trial, Fox 4 reported.

Cops discovered Grayson’s mangled body behind Grand Boulevard Lofts in downtown Kansas City just after 11 a.m.

He died at the scene from his horrific injuries.

During their investigation, police saw only one open window on the building’s entire wall, which led them to O’Connor’s top-floor unit — where they found the mother lying in front of the open window.

When asked where her son was, O’Connor admitted to cops that he “went out the window.”

Despite this, the mother did not call 911, according to court records reviewed by Fox, which said that a pedestrian alerted police to the incident.

Instead, O’Connor’s phone was found sitting on a counter, broken and unable to power on, KCTV reported, citing court records.

An eviction petition against O’Connor also revealed she had allegedly removed a safety device that would prevent the window from opening.

Investigators also found feces embedded into the carpet inside O’Connor’s apartment, no bed in the bedroom, and chocolate that was smeared on a windowsill with what appeared to be child handprints – which was dripping all the way down the building’s exterior to the ground, according to a probable cause statement reviewed by KCTV.

Following her arrest, O’Connor was originally charged with Class A endangering the welfare of a child, which required proof that she “knowingly” acted in a way that put the boy at risk. The charge was later amended, however, to Class C involuntary manslaughter, which only required prosecutors to prove that she “recklessly” caused Grayson’s death — a lower standard under Missouri law, the outlet reported.

The mother “knowingly acted in a manner that created a substantial risk to the life, body and health” of the boy by “failing to supervise” him while they “were together in a seventeenth-story apartment containing a fully open window,” which “resulted in death to the child,” the latest indictment stated.

Following O’Connor’s guilty plea this week, Jackson County Prosecutor Melesa Johnson said she hoped the grieving mother will get the help she needs in prison.

“The plea was reached after careful consideration of the evidence and circumstances of the case. A child lost their life and the decision allows for both accountability, while also acknowledging a mother who is now living in grief,” Johnson said.

“We also hope that during her time in custody, she will have access to the resources and support she needs.“