Family’s push for doctors to recognise ‘diabulimia’ as young woman tells of tragic toll

As young girls, Sienna Wiltshire and her big sister Tawny were inseparable.

Their infectious smiles and playful bond, captured in a childhood’s worth of photographs, promised a future of sisterly love to last a lifetime.

But pictures can’t tell how long lifetimes will be and they can’t see the fragility of faulty DNA lurking within one child, but not their sibling.

By the time Sienna was eight, she had been diagnosed with…