CHICAGO (CBS SF) — A Burlingame law firm on Thursday filed a wrongful death lawsuit against aircraft-maker Boeing over last month’s Ethiopian Airlines plane crash.

The firm of Cotchett, Pitre & McCarthy is representing the family of a passenger killed in the March 10 crash of Ethiopian Airlines Flight 302 involving a Boeing 737 Max airplane.

24-year-old Samya Stumo was an advocate for health care, and was traveling for work at the time of the crash.

Stumo was a niece of consumer advocate Ralph Nader.

Family members of Stumo and attorneys representing them held a news conference in Chicago Thursday morning.

“There are basic fundamentals to making sure a plane is safe,” said attorney Frank M. Pitre. “It starts with design and testing. That’s the responsibility of the manufacturer and in this particular case, the supplier.”

“My sister was intensely competitive and never wanted to be the second child in anything but age. As we grew, Sammy out stripped me in many ways,” said the victim’s brother Adnaan Stumo. “She had so much to teach me about compassion, self-awareness, sensitivity to others, focus and just straight life joyfulness.”

This is the first lawsuit filed on behalf of an American involved in the crash.

Meanwhile, Ethopian investigators said the pilots of that flight followed Boeing’s emergency procedures, but could not regain control of the plane.

Sources told CBS News they believe a sensor malfunction triggered an anti-stall feature on the 737 Max shortly after takeoff.

The pilots followed procedure and turned off the feature, but were still unable to regain control

They then appeared to deviate from guidelines by turning the system back on, pushing the plane into a dive.