The Real Housewives Of New York star revealed that her family were 'devastated' by the news.
She posted on the family website: "'With the heaviest of hearts, we are devastated to share the news that our beloved Bobby Zarin passed away peacefully today surrounded by family after a courageous battle with cancer."
"'There are no words to describe how heartbroken we are. Thank you, everyone for all your love, and support during this difficult time.'
Bobby Zarin was first diagnosed with thyroid cancer in 2009 – he had his thyroid removed as well as undergoing radioactive iodine treatment.
It's understood that his cancer returned last summer and he was receiving treatment in hospital after also having a brain tumor removed.
RadarOnline.com revealed how brave Jill, 53, had been keeping a bedside vigil beside her husband in recent days.
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