Police announced on Friday they've obtained a warrant charging Timothy Virts, the girl's father, with murder after discovering Bobbie Jo Cortez, 36, dead inside her Dundalk home on Thursday.
Their daughter, Caitlyn Virts, is reported missing along with her father.
According to police spokeswoman Elise Armacost, Caitlyn's twin sister and Cortez' young son, as well as two adults, were living at the home. She said Timothy Virts has also been staying there for the past several weeks.
Police say the mother's current husband is in jail on a pending case in court on charges relating to child sex abuse.
Maryland State Police sent an Amber Alert for Caitlyn on Thursday, about 90 minutes after Cortez' body was found, and a second Amber Alert was later issued in West Virginia.
Police believe Timothy Virts may have fled to McDowell County, West Virginia.
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