On a cold December day in 2013 Catherine Simpson received the phone call she had feared for years. Her little sister Tricia had been found dead in the farmhouse where she, Catherine and their sister Elizabeth were born - and where their family had lived for generations.

Tricia was 46 and had been stalked by depression all her life. Yet mental illness was a taboo subject within the family and although love was never lacking, there was a silence at its heart.

After Tricia died, Catherine found she had kept a lifetime of diaries. The words in them took her back to a past they had shared, but experienced so differently, and offered a thread to help explore the labyrinth of her sister's suicide.

When I had a Little Sister tells a story of sisters and sacrifice, grief and reclamation, and of the need to speak the unspeakable.