Now Playing: Mother of missing Iowa college student: ‘You can’t give up hope’
Now Playing: Body found in search for missing Iowa jogger Mollie Tibbetts
Now Playing: Authorities work to identify body found in search for Mollie Tibbetts
Now Playing: Trump awards Medal of Honor to airman who saved teammates from al-Qaeda attack
Now Playing: Teacher searches for a new kidney by asking drivers on the street
Now Playing: Accused Mollie Tibbetts killer makes first court appearance
Now Playing: Suspect led police to the body of Mollie Tibbetts
Now Playing: Judge denies bond for man accused of killing pregnant wife, daughters
Now Playing: Suspect arrested in case of missing Iowa student Mollie Tibbetts
Now Playing: Father in custody after 2 sons drown in river
Now Playing: Florida police searching for man seen on camera setting car on fire
Now Playing: Father dances with 2-year-old daughter after she undergoes chemotherapy
Now Playing: Surveillance video shows woman dragged, run over during robbery
Now Playing: Police helicopter crashes at training facility
Now Playing: News headlines today: Aug. 22, 2018
Now Playing: Houston bank employee charged with robbery for role in violent attack
Now Playing: Colorado man faces 9 felonies for alleged murders of pregnant wife, daughters
Now Playing: Undocumented immigrant charged with murder of missing Iowa woman
Now Playing: Video shows crash of police helicopter in Arkansas
Now Playing: Hurricane Lane strengthens to Category 5 storm as it nears Hawaii
Read More