Yesterday in the afternoon I think two people attempted to burglarize my mom's house?

My mom told me that yesterday at around 1pm (broad daylight), my father had left the house to go to the gym. So she was home alone with her granddaughter, when somebody rang the doorbell. she looked out the window from upstairs in the master bedroom, and saw a car with an unfamiliar female driver that was backed up into the driveway and parked. There was somebody at the front door who had rang the doorbell so my mom walked downstairs to open the door, but by the time my mom had arrived to the front door, there was then knocking/pounding at the back door (the entire backyard is enclosed by a fence, so in order for somebody to get to the back door they would have to hop the gate on the side of the house). My mom walked to the back door thinking it was just me or something (I am her son), and when she opened the back door it was a male stranger. My mom said the guy was startled by her opening the door, and he asked "does eddie live here?" and my mom, also startled, answered "NO!" and the guy immediately turned and very quickly walked away back toward the gate on the side of the house (the gate is not visible from the back door so my mom could not see him hopping the gate). My mom closed and locked the door and went back to the front of the house and the car with both strangers were gone. What do you think about this situation, what should we do?? I am very scared for my parents, as they are scared too.