Shafquat Saleem, 39, torched the flat in Wester Hailes, Edinburgh, during a family feud in June 2001.
Saleem was detained in 2011 after returning to the UK. She had been living in Ercan, Northern Cyprus.
Saleem's parents lived at the Wester Hailes address with her younger sister, two brothers and uncle Khalid.
Most relatives escaped the blaze unharmed but her brother Imran, 18, ended up trapped in a room and died.
Yesterday, Saleem was sentenced to 13 years in jail at the High Court in Aberdeen for killing her brother, with the help of others.
Sentencing, Lord Stewart told her: "The evidence is silent as to the exact part that you played in the plot; but the evidence does indicate that you were not the driving force."
At the High Court in Glasgow in December, Saleem was found guilty of wilful fireraising which resulted in the death of her brother and attempting to defeat the ends of justice.
She was also found guilty embezzling £34,327 from the sub-post office in Edinburgh where she worked.
Warrants were issued in 2002 for Saleem, her sister Rafath and brother Tanveer. Saleem was the only family member indicted over her brother's death.
Detective Chief Superintendent Gill Imery, head of CID at Lothian and Borders Police, said: "I am pleased that, after more than 11 years, she has been brought to justice for her actions."