Both also were found guilty of assault of a child for punishing a boy they adopted in 2008 from Ethiopia at the same time as Hana.
Both appeared in court in red jail uniforms and were led away in handcuffs after the sentencing.
The courtroom was filled with many Ethiopians and nine of the jurors who convicted Larry and Carri Williams after a seven-week trial. Defence lawyers told jurors that questionable parenting practices didn't necessarily amount to a crime.
On the rainy night Hana died, Carri Williams called emergency services and reported Hana was not breathing, saying the girl had refused to come into the house. Hana was found face-down in the backyard with mud in her mouth.
Hana is believed to have been 13, but no documentation of her birth in Ethiopia was available.
The trial was postponed several times, and her body was exhumed in January. Tests on her teeth and bones gave varying estimates, and experts were unable to agree on her age. Her age was significant because the homicide by abuse charge applies only if the victim was younger than 16.
The boy from Ethiopia testified that the parents used sticks or belts to beat him all over his body as punishment. He also described being sprayed with a water hose if he wet his pants.
After the arrests, the boy and six biological children were placed in foster care or with relatives.
- AP