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Filmmaker and journalist Barbara Sumner was adopted in 1960 and at the age of 23, embarked on a search to find her birth mother.
The system made this all but impossible, and Sumner now campaigns for an overhaul of New Zealand's 'closed' adoption laws.
She's chronicled her journey in a memoir Tree of Strangers.
Sumner and her husband Tom Burstyn are the makers of the critically acclaimed 2009 documentary film, This Way Of Life, about a family of horse breeders living near the Ruahine Ranges.
Barbara Sumner Photo: supplied