Now Playing: Study finds there has been a spike in pregnant women using marijuana
Now Playing: Sessions explains his opinion of marijuana users
Now Playing: Parts of East Coast buried in snow and ice
Now Playing: Woman arrested for giving marijuana to 1-year-old
Now Playing: Suspected serial bomber killed himself as SWAT was closing in: Authorities
Now Playing: Springtime snowstorm cuts miserable path through Northeast
Now Playing: Loyola-Chicago’s secret weapon: Sister Jean
Now Playing: Mueller team zeroing in on political consulting firm with Trump ties: Sources
Now Playing: Authorities ID 23-year-old Austin man as alleged serial bomber
Now Playing: Austin serial bombing suspect left 25-minute ‘confession’ on phone: Police
Now Playing: Video shows moments before self-driving car hit pedestrian
Now Playing: Bus driver almost crashes into home after being stabbed in neck
Now Playing: Workers adjusting 2 of bridge’s tension rods when span collapsed: NTSB
Now Playing: Unarmed man killed by police who fired 20 rounds at him
Now Playing: See the horrifying damage after deadly southern California mudslides
Now Playing: 1st days of spring bring massive snowstorms to the East Coast
Now Playing: Spring nor’easter slams East Coast, will pummel major cities during rush hour
Now Playing: ‘GMA’ Hot List: Richard Branson shares advice for how to make a ‘positive difference’
Now Playing: 12-year-old boy killed after being caught in lazy river suction line
Now Playing: 4th nor’easter in a month pelts Philadelphia with snow