The mom of a 2-year-old boy who was struck and killed by a subway train over a year ago is suing the MTA and a train conductor over the incident, new court papers show.

Shayla Sowell had been with her son Shamari Anderson inside the Fulton Street Station on Dec. 11, 2019, when the tot slipped away from her and lost his footing as a northbound 2 train was approaching.

The suit says that the operator was negligent and should have known that the mother and child “were near the edge of the platform and had the opportunity with the use of reasonable care to slow or stop the train or warn the plaintiffs before the train struck [Anderson] while he was still on the platform,” a Manhattan Supreme Court lawsuit from Tuesday alleges.

Anderson, “was struck, mangled and eventually died due to the catastrophic injuries he sustained,” the court papers claim.

Sowell says that in the last 15 years there have been hundreds of deaths and thousands of injuries due to people being hit by subway trains, the court documents claim. And the transit authority should have installed platform edge protection which it knew “would save lives and injuries,” the suit charges.

The MTA has “actually attempted to shift the nondelegable duty to keep their subway stations safe” by using signs to tell people that they should help anyone who looks sick or intoxicated from falling onto the tracks, the court documents claim.

“Authorities should be stripped of their shield of immunity and the authorities should be required to accept responsibly for disregarding their sacred obligation of public safety,” the court filing alleges.

Sowell has had to undergo “extensive therapy” for severe emotional stress “caused by the contemporaneous witnessing of her son being crushed by a train,” the court papers say.

Sowell is suing for unspecified damages.

Her lawyer did not immediately return requests for comment.

The MTA said, “We don’t comment on pending litigation.”

Additional reporting by Craig McCarthy