America's fastest miler isn't dwelling on his past.
She is the older sister of two-time Olympic gold medalist, Tirunesh Dibaba.
She had tested positive for EPO in 2009.
He wants to become the first American male winner since 1986.
She will be racing in South Carolina this weekend.
She hopes to use the London Marathon as a springboard.
They've known each other for 15 years.