She received a personal request from New Zealand's Prime Minister John Key to perform at the city's memorial service, where the prince is expected to address the congregation.
Meanwhile, Westenra has unveiled details about Quake Aid, a star-studded benefit concert she's organising to raise much-needed funds for the local community as residents try to rebuild their lives in the wake of the tragedy.
She said, "Putting on these concerts is the best way I know to help - it’s my way of giving back to the city that means so much to me."
Westenra scrapped a scheduled tour of New Zealand in order to plan the charity show. It will take place in Auckland in August (11), with all proceeds going to earthquake relief.