The embarrassing news just keeps coming for Stanford University.  A teacher at the Children's Center of the Stanford Community, an on-campus daycare center, was arrested as her tiny students were napping.  The charge: murder.

Andrea Vacchiano reports for Fox News:

A preschool teacher who worked on the campus of Stanford University was arrested for murder last week, along with her friend, according to authorities.

Santa Cruz resident Diana Ornelas, 22, was arrested on Wednesday along with her friend, Dennis Novoa, 27.

The pair allegedly shot and killed 24-year-old Oliver Waterfall in Santa Cruz County in California on April 11. His body was found on a hillside off Highway 9.

Authorities said in a statement that they believe the motive for the killing was "of a personal nature" as Ornelas and Novoa apparently knew Waterfall.

Ornelas taught at the Children's Center of the Stanford Community, a child care center on campus. A Stanford University spokesperson said Ornelas was arrested at nap time.

"The arrest happened at nap time and outside of the perimeter of the CCSC campus. Children were not present when this occurred, and it did not disrupt operations," the spokesperson told student newspaper the Stanford Daily.

Diana Ornelas (Santa Cruz Country Sheriff's Office).

As a parent who had a child in a university daycare center in the ancient past, I expect that the parents of the Stanford kids are appalled that their little ones were in the care of an accused murderer.  "Vengeful murderer based on personal issues" is not among the personal qualities sought in daycare providers.