A California woman faces homicide and assault charges in the death of a six-week-old infant she was babysitting in Pittsburgh and injuries sustained by the infant’s twin brother. Nicole Virzi, 29, of San Diego, was arrested after police responded to a call on Saturday night reporting that a baby had fallen from a bassinet. The infant was rushed to UPMC Children’s Hospital but died shortly after. Medical examination revealed a severe skull fracture and brain bleeds; injuries deemed inconsistent with an accidental fall. Read: Florida Convicted Murderer Gets Death Penalty In 2012 Slaying Of 19-Ye…