Now Playing: Prince Philip's final public engagement before retirement announced

Now Playing: Princess Diana's brother 'lied to' over coffin walk at her funeral

Now Playing: New report finds brain disease in most football players studied

Now Playing: Harrison Ford: 'Blade Runner 2049' is a 'fantastic ride'

Now Playing: Trump tries to rally Republicans on health care bill

Now Playing: New survey sheds light on the US fertility rate

Now Playing: What to skip and what to swap at the supermarket

Now Playing: Is it wrong to talk while watching TV?

Now Playing: Travel blogger challenges strangers to find him at the airport to score his upgraded seats

Now Playing: 12-year-old who started a lemonade stand at age 4 shares her business tips

Now Playing: Corey Lewandowski on Trump's attacks against Jeff Sessions

Now Playing: Newly released video shows California inmates' escape

Now Playing: Family speaks out after daughter dies at Mexico resort

Now Playing: 'Dance Moms' star shares her final moments before reporting to prison

Now Playing: Trump leaves open possibility of firing Sessions

Now Playing: Tinder couple whose 3 years of messages went viral describe their surreal 1st meeting

Now Playing: 'GMA' Hot List: CDC reveals fertility rate in the US is at all-time low

Now Playing: NFL player Lucky Whitehead says he was 'angry,' 'blindsided' after being released by Dallas Cowboys

Now Playing: Chicago Bears player saves choking stranger

Now Playing: Johnny Depp claims ex-managers trying to 'publicly vilify' him