The children of late violinist Isaac Stern are suing the former executor of his estate for more than $2m (£1.03m).
World famous violinist Isaac Stern died in 2001
They say William Moorhead improperly calculated the estate's value and sold many of Stern's personal items.
Stern, who died in 2001, was among the most respected classical musicians in history and credited with discovering Itzhak Perlman and cellist Yo-Yo Ma.
Shira Stern, the violinist's daughter, said her father's legacy had been "needlessly squandered".
"We're doing this because this individual, in the guise of doing what he should be doing, took advantage of a situation," she added.
Stern's children said they were not contesting their father's will, but the actions of Mr Moorhead.
They said he had given Stern's New York City apartment to his wife instead of accounting for it in the estate.
If Mr Moorhead had accounted for the apartment's $3.7m value, "there never would have been any need to auction off Isaac Stern's legacy," said Mark D
Schwartz, the children's solicitor.
Mr Moorhead, who has resigned as executor, was not available for comment.
Stern lived in Connecticut at the time of his death. He had an apartment in New York City and a family home in New Milford.
Stern's children said they had learned the items were on the market when a Philadelphia musician called Stern's son, Michael, and inquired about a violin he saw on the internet.
"When you think about the stature of our father, to put it up on the internet like some glorified garage sale was unfortunate to say the least," said Michael Stern, who
takes over as music director of the Kansas City Symphony next year.
Court documents show Stern signed the apartment over to his wife in the final weeks of his life.
He was in hospital at the time and, his children say, not fit to make decisions.
"It's time to remember him the way he would want to remembered, and the way we want to remember him," Shira Stern said.
"This chapter needs to be closed. It cannot continue to hang."