After several rounds of motions and appeals looking to delay or prevent incarceration, Anthony D. Marshall, the 89-year-old son of Manhattan billionaire Brooke Astor, has begun a prison sentence for stealing millions of dollars from his mother.

Marshall was convicted in 2009, alongside Astor family lawyer Francis X. Morrissey Jr., of altering his mother’s will to leave himself tens of millions of dollars. Astor, who died in 2007 at the age of 105, was more than 100 at the time and suffering from Alzheimer’s.

The case has raised awareness of both elder abuse and the potential legal complications resulting from Alzheimer’s and dementia—and old age continues to be a theme in the case. Lawyers for Marshall, who suffers from Parkinson’s and heart problems, released a statement lamenting that the octogenarian must serve prison time. “Incarceration will simply make his final days more tortured and undoubtedly fewer in number,” it said.

Read more at the New York Times.