Musician Joe Henry, who is married to Madonna's sister Melanie Ciccone, shared the news on Instagram along with a black and white photo of him.

He wrote: "My brother-in-law, Anthony Gerard Ciccone, exited this earthly plane last evening.

"I've known him since I was 15, in the spring of our lives in Michigan so many years now gone.

"Anthony was a complex character; and God knows we tangled in moments, as true brothers can. But I loved him, and understood him better than I was sometimes willing to let on."

The cause of death was not revealed. However, Ciccone was known to have struggled with alcoholism and was reportedly homeless for many years.

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As the eldest boy of the family he had been named after his father, while Madonna, as the eldest girl was named after her mother.

Along with their siblings, they were born and brought up in Michigan. In 1978 Madonna left to pursue a career in New York, while Ciccone remained in their home town.

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Ciccone had at times been estranged from his family, and had also spent time living at a rehabilitation facility.

Henry's post announcing Ciccone's death nodded to those difficulties, saying "trouble fades", family remains, with "hands reached" across the table.

Madonna liked the Instagram post but did not comment on it.