Three American friends, Sarah Shourd, Shane Bauer and Joshua Fattal have been imprisoned without charge in Tehran since 31 July 2009. They were hiking near the border between Iraq and Iran when they were detained.
This week, the US Secretary of State Hilary Clinton has once again called for their release and asked that they be allowed to return to their families.
Sarah's mother Nora has been campaigning ardently for their release for the past year.
During this time she has only had patchy contact with her daughter but has learnt that after a prison yard proposal Sarah and Shane are engaged to be married.
Matthew Bannister spoke to Nora about Sarah's ill health and depression, and the effect Sarah's imprisonment has had on her own life.