Now Playing: President George H.W. Bush honors wife with 'crazy socks'

Now Playing: Young giraffe back with her mother at zoo after escape

Now Playing: Live update on the police shooting in Dallas

Now Playing: Suspect arrested in decades-old 'Golden State Killer' case: Sources

Now Playing: Former police officer, 72, arrested in decades-old 'Golden State Killer' case

Now Playing: Sanders addresses allegations against Pruitt

Now Playing: Weather radar picks up widespread bird migration

Now Playing: Video shows frantic pool rescue of boy trapped underwater in lazy river

Now Playing: Former transit commissioner resigns after vulgar rant during traffic stop

Now Playing: Police investigating pit bull attack on NYC subway

Now Playing: Woman kills husband's mistress, herself: Police

Now Playing: Video shows Florida high school officer body slam student

Now Playing: Dallas police officer dies 1 day after shooting that injured 2 others: Officials

Now Playing: Sean Spicer unveils Melania Trump's wax figure at Madame Tussaud's

Now Playing: Manhunt underway for person of interest in shooting of 2 police officers, civilian

Now Playing: Teen murders his mother with help from friends, authorities say

Now Playing: Boy, 5, says teachers taped his mouth shut, threw away his lunch

Now Playing: Sweet find as 50,000 honey bees colonize Ohio garage

Now Playing: Live update on the deadly van attack in Toronto

Now Playing: Colorado lawmakers propose jail for teachers on strike