Kamaljeet Rehal, from Birmingham, is waiting for a visa before flying to New Delhi where her relatives are mounting a round-the-clock vigil at the city's airport. Her brother, 31, a community worker, who lives in India, is spending his sixth day on board the A300 Airbus.
Mrs Rehal's brother, whom the family do not want to name for fear of repercussions, was returning from a business trip when the hijack occurred.
The Indian Airlines jet with 160 people on board is at Kandahar airport in Afghanistan where Indian officials are negotiating with the hijackers.
Yesterday Mrs Rehal's husband, Gurmeet, told reporters that the family in Britain and India was "devastated" by the news and that was a deciding factor in his wife's decision to join relatives.
"My wife is flying out to New Delhi to be with her family. She wants to be with them. Her heart is with them. We're just waiting for a visa to come through," he said.
"It's been pretty sombre over the last few days. Our Christmas just died the moment we heard the news. One minute we were laughing and joking and listening to music, then we were watching the news."