20/20: My Extreme Affliction (2)

Topics include growing up with parents who are hoarders; women who keep many cats; and alopecia, a condition that produces sudden and unpredictable hair loss. Also: a Barbara Walters report on progeria, a rare disease that causes children to age rapidly. Walters focuses on two girls who were also profiled in "6 Going on 60," a December 2009 TLC documentary.

Source: ABC