Diagnosing Loss of Power in Bedroom
Since you state, "When she unplugged it, the lights went out in the room," this seems like the inductive "kick" caused by breaking the circuit caused the issue, rather than overload from the heater. 

Look for a Ground Fault Circuit Interrupter (GFCI or GFI) like that in the image below. These outlets are designed to help prevent electric shock, but are also sensitive to sudden surges. Since they're usually specified in wet locations, the outlet might be in a basement or bathroom, but wired to provide protection in the bedroom.