The 11-year-old cheerleader who was shot to death by her mother in a harrowing murder-suicide was found with her face covered by a pillow that had a bullet hole through it, gruesome autopsy reports show.

Las Vegas cops discovered Addilyn Smith and her 34-year-old mother, Tawnia McGeehan, dead from gunshot wounds to the head while performing a welfare check on the Utah duo inside their hotel room at the Rio Hotel and Casino on Feb. 15.

The relatives’ lifeless bodies were found lying side-by-side on one of the beds inside the hotel room, where investigators also found a series of deranged, handwritten suicide notes left behind by the twisted mother – including one taped to a chair near the entrance that read: “Call 911 before walking in. Two dead bodies and one is an 11-year-old,” according to Clark County autopsy reports obtained by The Post.

Toxicology results included in the newly released reports also show that the mother-daughter duo had ingested a myriad of drugs before the gunfire erupted.

Substances including quetiapine, an antipsychotic medication; gabapentin, an anticonvulsant drug used to treat seizure disorders; the anxiety drug lorazepam and the antihistamine diphenhydramine were all present in Smith’s system when she died.

McGeehan’s toxicology report listed the same drugs, as well as eszopiclone or zopiclone, a prescription sedative; the antidepressant drug known as citalopram or escitalopram; desmethyl loperamide, a chemical breakdown caused by the anti-diarrhea medication loperamide and cannabinoids.