A jury in Girona rejected the argument by Lianne Smith's lawyer that she was mentally disturbed when she smothered her daughter, Rebecca, 5, and son, Martin, 11 months, in 2010, The Independent reported. Smith, who was staying at a hotel in Lloret de Mar, tried to kill herself after she killed the children.
Lianne and Martin Smith moved to Spain in 2007 from Lichfield in the English Midlands after Sarah Richardson, Smith's daughter from a previous marriage, said Martin had raped her.
Martin Smith was arrested in Barcelona shortly before the children were killed May 17, 2010.
Richardson has gone public about the sexual assault.
Martin Smith, who was convicted in Manchester in December 2010, hanged himself in Strangeways Prison there in January.
Lianne Smith's lawyer argued she feared authorities would seize her children.