A COUPLE who fed their infant daughter an extreme vegan diet that led to her developing rickets have admitted causing her injury.

The child would be restricted to a cup of oats with rice milk and half a banana for breakfast, a piece of toast with jam or peanut butter for lunch and tofu, rice or potatoes for dinner.

But her diet was so poor she developed degenerative bone disease as a result of malnourishment.

Her father, 34, and 32-year-old mother pleaded guilty to failing to provide for a child, causing serious injury, The Daily Telegraph reported.

A court in Sydney, Australia heard the girl was admitted to hospital in March this year after suffering a seizure and her mother told a dietitian her entire family followed a vegan diet.

Her levels of vitamin D, which can cause bone disease if found to be too low, were “undetectable”.

She had fractures scattered throughout her tiny body and her bones were so brittle doctors believed they could have been broken by “normal handling”.

A doctor described her as “floppy” who noted she was unable crawl or talk during her month being treated in hospital.

Aged one, the child weighed only 10lbs which was barely double of what she weighed when she was born.

The court was told hospital staff initially respected her unnamed parents’ choice of diet but their concerns began to grow.

The parents exchanged text messages denying their daughter's lack of growth was a result of malnutrition, the court was told.

Police asked her dad why he wasn't concerned that his daughter never grew and he replied that she was just “petite”.

Doctors found an absence of immunisations, no follow-up check-ups after she was born and no birth certificate.

The now 19-month-old girl is now in foster care with her two older brothers, aged four and six.

She has put on 13lb and is crawling and standing on her own after six months.

Her parents will return to court on January 16 to be sentenced.

Earlier this month, Tammi Bleimeyer was jailed for 28 years after starving her stepson and making him wear a nappy at their home in the town of Spring.

The 37-year-old, from Texas, was found guilty of injury to a child by omission after forcing Jordan Bleimeyer, now aged nine, to sleep in the tiny crawlspace under the stairs with his lone mattress surrounded by exposed nails and wiring.