Now Playing: Bodyguards on the King of Pop

Now Playing: Schools face threats after deadly high school shooting

Now Playing: New storms build in the South

Now Playing: Rosenstein agrees to Trump 'demand' for probe: WH

Now Playing: Congratulations, Maddie Poppe

Now Playing: Bachelorette Becca Kufrin is engaged

Now Playing: 'American Idol' runner-up and winner reveal relationship

Now Playing: 7 firefighter colleagues welcome babies within months of each other

Now Playing: These are the 25 most famous women athletes in the world right now

Now Playing: Bishop describes powerful sermon at Harry, Meghan's wedding

Now Playing: Harry, Meghan to make 1st post-wedding appearance

Now Playing: 'American Idol' finalist Caleb Lee Hutchinson performs live on 'GMA'

Now Playing: 'DWTS' champ Adam Rippon and 'American Idol' winner Maddie Poppe talk victories

Now Playing: 'American Idol' finalist on competing against girlfriend Maddie Poppe

Now Playing: 'DWTS' winner Adam Rippon, finalist Tonya Harding talk season 26 finale

Now Playing: Parents take son to court to get him to move out

Now Playing: Manhunt underway after cop killed in line of duty

Now Playing: Toxic cloud prompts warning in Hawaii volcano emergency

Now Playing: Olympian sues USA swimming over alleged sexual abuse cover-up

Now Playing: 'Idol' and 'DWTS' finalists face-off in 'Sync or Spin'