An apparently suicidal, mentally disturbed woman and her two retarded sons were burnt to death yesterday in the western Athens prefabricated house the family had inhabited since their home was destroyed by earthquake in 1999. Maria Kalogera, a 53-year-old mother of five, and her sons Spyros, 31, and Antonis, 30, lived in a camp in Kipoupoli built to temporarily house people whose homes were rendered uninhabitable by the 5.9-Richter quake three and a half years ago. The woman’s brother Giorgos, who is reportedly also mentally retarded, told firemen his sister put him out of the house around noon yesterday, telling him what was about to happen was not his business. She then apparently doused herself and her children with methylated spirits and set all three alight. Neighbors managed to extinguish the blaze, but were too late to save the three.