Girl critical but stable after train jump

Three-year-old Shreya Kunnath is still fighting for her life in a Sydney hospital days after her mother jumped in front of a train while holding her in the city's west.

Archana Kunnath died on Wednesday afternoon after the incident at Harris Park train station.

CCTV footage of the incident shows Ms Kunnath, 30, deliberately stepping into the path of the oncoming train, police say.

Her daughter was pulled alive from under the train, and remains at the Children's Hospital at Westmead in a critical but stable condition.

The young mother was an assistant software engineer at Tata Consultancy Services, where her husband Sujith Vaikakkara also worked.

"The TCS community is shocked and deeply saddened by this tragedy. Our thoughts are with Archana's family and friends at this time," CEO Deborah Hadwen said in a statement.

Ms Kunnath and her husband celebrated their fifth wedding anniversary just five days before she died.

Pictures posted to Facebook show her smiling and holding her daughter outside the Sydney Opera House and Harbour Bridge, and travelling with her husband.

On Saturday Mr Vaikakkara posted on a now-deleted Facebook page about the couple's wedding anniversary, NewsCorp has reported.

"5 years of togetherness...Thanks and prayers to Almighty," he wrote.

With a photo of his daughter on her birthday he wrote: "It's been 3 years after we blessed with this gods gift".

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