The flames erupted from the home around 4 a.m. on the 300 block of Margaret Road back on April 4.
Eva and Ava Brown-Williams, 5, were found in their upstairs bedroom. The family says they died in their sleep.
Their mother, Robyn Brown, was able to jump out of a back window when the fire broke out, which caused her numerous fractures.
Two firefighters also suffered non-life-threatening injuries in the blaze.
Chief Sawyer said it is important to make sure your home has working smoke alarms. He also urged everyone to have a fire escape plan and to close bedroom doors when sleeping.