Madonna's Older Brother Anthony Ciccone Dead at 66 After Decline in 'Past Few Months': Source

Splash News Madonna's older brother Anthony poses for a photo in Traverse City, Michigan

Madonna's older brother, Anthony Ciccone, has died, PEOPLE confirms. He was 66.

The musician's brother-in-law, Joe Henry — who is married to Madonna's sister, Melanie Ciccone — announced the news of Anthony's death Saturday on Instagram, where he described Anthony, one of Madonna's seven siblings, as a "complex character."

"My brother-in-law, Anthony Gerard Ciccone, exited this earthly plane last evening," Henry wrote in his caption. "I've known him since I was 15, in the spring of our lives in Michigan so many years now gone. As brother Dave Henry (who took this photograph) notes here, 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," he continued. "But trouble fades; and family remains— with hands reached across the table. Farewell, then, brother Anthony. I want to think the god your blessed mother (and mine) believed in has her there, waiting to receive you. At least for today, no one shall dissuade me from this vision."

Reps for Madonna have not commented on the news.

A source tells PEOPLE the pop superstar and her family had a complicated relationship with Anthony because of his struggles.

"They were all there for him and despite being estranged, Madonna supported him in every way she could when he was willing to take the support," says the source. "Family members including Madonna visited him while in his rehab facility as he declined these past few months."

Ethan Miller/Getty Madonna

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RELATED: Madonna's Older Brother Says He's Homeless

Madonna grew up in Michigan, where her brother is believed to have died, Page Six reported.

In 2011, Anthony spoke out in an interview, saying he was "homeless on the street" and living under a bridge in Michigan.

Madonna's brother Christopher later confirmed that Anthony was "back home" and "recovering" following some time in a treatment center.