UPDATE: A grimly determined <strong>John Travolta </strong>will testify in the multi-million dollar extortion blackmail trial in the Bahamas.

RadarOnline.com reports that insiders claim that Travolta has been dreading appearing at the extortion trial because it could reveal private details of his autistic son Jett's death and bring back heartbreaking memories of the tragedy for both the star and his family.

But it's now been confirmed he will testify.

On September 11, 2009 John, wife Kelly Preston and daughter Ella Bleu, 9, made their first public appearance since Jett's death at Disney's D23 Expo to promo new flick Old Dogs in which they all star.

CLICK HERE for all the details of the blackmail trial in which paramedic Tarino Lightbourne and Pleasant Bridgewater have already plead not guilty to charges they tried to extort $25 million from the reclusive superstar.

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