The dad, Hamad Saoud al Sherawi, 29, and his mistress Al Anood al Ameri, 27, were convicted of illegal confinement and gross torture of Wadeema, eight, leading to her death and subjecting her sister Meera, seven, to physical and emotional abuse.
They had locked up the girls in the toilet and forced them to consume their own waste.
Wadeema died of her horrific injuries after being burnt with an iron and cigarettes and having hot water poured on her shaved head. She was also given shocks with electric rods and whipped with cables.
Meera was left with a 10 per cent permanent deformity related to a fracture in her right upper arm among other injuries.
Dubai Criminal Court referred to the Maliki School of Law insisting that a parent deserves the death sentence should there be an intention.
"In this case, there was a probabilistic intention as the duo should have realised that the excessive torture could consequently lead to death," the ruling read.
Al Onoud has been jailed for life.