A 7-year-old girl who died unexpectedly after a medical emergency on a Wayzata dock on Sunday was killed by carbon monoxide poisoning, family members said Monday.

Emergency crews were called to a dock on Wayzata Bay on Sunday night and found Sophia Baechler of Edina unresponsive.

First responders took Sophia to Hennepin County Medical Center, where she died.

“Sophia was an amazing little girl filled with overflowing kindness and love for others. She brought out the best in all those around her,” her family said in a statement Monday night. “She will be forever remembered in our hearts.”

It’s unclear whether she had been on a boat or what exactly caused the carbon monoxide poisoning.

Carbon monoxide poisoning from a boat is fairly rare, according to the Minnesota Department of Natural Resources (DNR). In the past eight years, it has only happened twice, according to state data, both in 2013. That year, a 44-year-old Champlin man and a 35-year-old Long Lake man died while boating on Lake of the Woods from carbon monoxide poisoning from a faulty exhaust system on the boat.

The Hennepin County Sheriff’s Office is still investigating the case.

Sophia was a second-grader at Concord Elementary School in Edina. In a letter to the school’s parents Monday, the principal confirmed her cause of death to dispel any rumors. The school district’s crisis response team, including counselors and social workers, are on hand this week to help grieving young classmates.

On Lake Minnetonka, the Minnetonka Power Squadron hosts public boating safety classes that include how to prevent carbon monoxide poisoning. While many newer boats have carbon monoxide detectors, it isn’t required in boats, said Steve Leighton, a vessel safety examiner with the group. “It’s certainly a tragic situation,” Leighton said.

He added that he doesn’t know any specifics of Sunday’s situation but that he generally advises people to be aware of exhaust fumes and have a carbon monoxide detector on a boat. “I wouldn’t have a boat without one … just like my house,” he said. “The exhaust fumes are always a consideration.”

Carbon monoxide can build up on a boat from an idling motor, a generator or from a faulty motor exhaust system, as in the 2013 case.

The DNR advises boaters not to leave motors idling or generators running while anchored or docked. Boaters also shouldn’t sit on the swim deck on the back of the boat while the motor is running and should stay back at least 20 feet while being towed for water skiing or tubing. Boat owners should make sure motors and exhaust systems are maintained annually, the DNR says.

Common symptoms of carbon monoxide poisoning are headaches, dizziness, weakness, nausea, vomiting, chest pain and confusion.