A lawyer for Laura Freeman filed a notice of claim against the city and several agencies Wednesday. The notice is the first step in filing a civil suit.
Lawyer Sanford Rubenstein says Yvonne Freeman died from a heart attack on Dec. 27 while waiting hours for an ambulance.
Laura Freeman plans to file a $20 million wrongful-death lawsuit.
The city's Law Department says the case involves a "tragic situation." It says it's awaiting the legal papers.
The blizzard dumped 20 inches of snow in some parts of the city.
Mayor Michael Bloomberg has said the city's cleanup was handled poorly.