Excerpts from abc7chicago.com:

The Greater Round Lake Fire Protection District was dispatched to the 100 block of West Providence Lane in Round Lake for a report of a structure fire at 9:48 a.m. on Saturday morning after a neighbor saw dark colored smoke coming from the roof.

Firefighters entered the structure, a two-story duplex residence, and found a female occupant on the second floor. She was transported to Advocate Condell Medical Center, where she later died. Two dogs were rescued from the residence and one survived. 

The fire appeared to originate on the first floor in the kitchen area. The Greater Round Lake Fire Prevention Bureau, in conjunction with the Round Lake Police Department and the Office of the Illinois State Fire Marshal, is investigating the cause of the fire.