The FBI and Maryland State Police are searching for two women last seen in early April who have ties to accused murderers. Heather Grogg, 33, worked as a live-in babysitter at the home of David Sanford Jr., one of three men charged in the March 18 murder of Jonathan Riddle. In the midst of an argument, Riddle was stabbed twice at Sanford's home, then taken to a rural area in West Virginia, where he was fatally stabbed and set on fire, according to police. Grogg seemed shocked by Riddle's murder, her sister tells NBC News. But "I'm worried she witnessed something she shouldn't have seen," says Brandie Hebb. "It's not like her to just disappear." Hebb last heard from her sister, a mother of four, on April 3. Grogg "seemed a little stressed" and "wanted to see me face-to face," but the sisters opted to forgo a meeting owing to the statewide stay-at-home order.
Authorities believe Grogg may be with the other missing woman, 18-year-old Danielle Tyler, who frequented Sanford's home and was dating another of the murder suspects, Monroe Merrell, with whom Riddle apparently argued. Grogg and Tyler were last seen together in Carroll County on April 6, days before the suspects were arrested, per CBS Baltimore. That was also the last time Tyler's grandmother heard from the high school senior. "I think I am going to turn my phone off for a little bit … I am just tired of all the drama," Tyler wrote in a text, per People. Sherry Tyler later filed a missing persons report at the urging of homicide detectives. "I am scared to death," she tells the Baltimore Sun. "I am afraid that maybe she saw something, these girls saw something." State police say the women are "considered to be critically missing and in danger." (Read more missing persons stories.)