Sperm-donors' kids seek more rights and respect

Katrina Clark and Lindsay Greenawalt have much in common. Bright women in their 20s, raised by single mothers, keenly curious about the men whose donated sperm helped give them life. Clark's search for her father succeeded after only a month, though with a bittersweet aftermath. Greenawalt is still searching, seven years after she started — persisting despite doubts and frustrations.