A son-in-law of indicted former New York Assembly Speaker Sheldon Silver was sentenced to two years in prison on Wednesday for running a Ponzi scheme that defrauded investors out of nearly $6 million.

Marcello Trebitsch, 38, was also ordered by U.S. District Judge Vernon Broderick in Manhattan to forfeit $5.9 million, Manhattan U.S. Attorney Preet Bharara's office announced.

"We are very pleased that Judge Broderick imposed a sentence substantially below the 51-63 (month) sentence requested by the government, but it still breaks my heart to see a man like Marcello Trebitsch go to prison," Trebitsch's attorney, Benjamin Brafman, said in an email.

The sentencing came three weeks after Trebitsch's father-in-law, Sheldon, was found guilty in a separate case of abusing his office to collect $4 million in bribes and kickbacks.

Trebitsch, a Brooklyn resident, pleaded guilty in July to securities fraud in connection with investment fund Allese Capital LLC, which he co-owned with his wife, Michelle Trebitsch, a daughter of Silver. Michelle Trebitsch is not accused of any wrongdoing.

Prosecutors said that from 2007 to 2014, Marcello Trebitsch solicited more than $8 million from four investors to be invested in large-cap stocks with the promise of annual returns of 14 percent to 16 percent.

But Trebitsch only invested some of the funds in securities, on which he suffered net trading losses, authorities said.

Trebitsch created false documents that claimed positive annual returns of 15 percent to 19 percent, prosecutors said. He used the rest of the investors' money mostly for his own personal benefit, including to repay other investors, prosecutors said.

The case was separate from the pending charges against Silver, 71, who was once one of the most powerful politicians in New York state and was one of two former New York state legislative leaders convicted in corruption trials this month.

The other, former New York Senate Majority Leader Dean Skelos, was found guilty of bribery and extortion on Friday.