Mother Teresa's Impact on the World

It's 20 years since the pioneering Roman Catholic nun retired from her work with the poor of Calcutta shortly before she died at the age of 87. Rebecca Kesby has been speaking to a woman who used to volunteer at the Mother Teresa orphanage. Plus we'll get an insight into life in the White House in the 1930s. We'll look at the birth of an African film industry and the immortal cells of Henrietta Lacks.