Mary Ann Murphy, 48, was found dead in her Humble home back in July. Her own 16-year-old daughter and a second person, Zein Ahmed, were already charged in Murphy's murder. Now, Ahmed's girlfriend, 20-year-old Rebecca Keller, has also been charged.
Keller told investigators Murphy's daughter asked her to help kill her mother.
Keller is also charged with sexual assault for having a relationship with the daughter.
She is in Harris County Jail on bonds totaling $80,000.