Now Playing: Woman Turns to Facebook in Quest to Find Birth Mom

Now Playing: Girl, 2, to Get Kidney From Complete Stranger

Now Playing: Mark Zuckerberg's Wealth Grows as Facebook Turns 10

Now Playing: Moon Rocks and Asteroids at NASA's Johnson Space Center

Now Playing: Upgrade to Emergency Smartphone Alerts

Now Playing: New Sexual Consent App Sparks Controversy

Now Playing: End of an Era: Blackberry is Done Building Smartphones

Now Playing: Elon Musk Unveils His Plan For Colonizing Mars

Now Playing: SpaceX Unveils Plan for Manned Mars Mission

Now Playing: Biggest Moments on Social Media From the Debate

Now Playing: Clinton, Trump Debate Cybersecurity, Hacks

Now Playing: Snapchat Now Offering Camera-Equipped Sunglasses

Now Playing: Families Challenged to a 'No Text Weekend'

Now Playing: Yahoo Reveals Huge Cybersecurity Breach

Now Playing: Massive Yahoo Hack Affects 500M User Accounts

Now Playing: Facebook CEO and Wife Announce Multibillion Dollar Initiative to Cure Diseases

Now Playing: A Look at the World's Most Powerful Telescope

Now Playing: The World Comes Together to Create a Next-Generation Telescope

Now Playing: At NASA Space Flight Center, A Successor to the Hubble Telescope

Now Playing: Music Matching Comes to Tinder