Ilya and Sophia Tsaruk were on vacation in Hawaii and had left their 18-month-old, Logan, with relatives, the GoFundMe page said. The Tsaruks lived in Snohomish, Washington, according to KING5 in Seattle.

On Saturday at 12 p.m., the Maui County Fire Department responded to a report of swimmers struggling in the waters of the Ahihi-Kinau Natural Area Reserve, located in the island's southwest corner, 6 miles south of Wailea, according to a news release. The reserve is a popular spot for snorkeling, as it still has intact coral colonies, according to Dan Dennison, a spokesperson for the Hawaii Department of Land and Natural Resources.

"The only thing I found challenging in that area is it's hard to get in the ocean there because it's a rocky coastline," he noted. Dennison added that there is no lifeguard stationed in the area, though signage on ocean safety is posted. Dennison said it's advised that people never snorkel alone, so this couple was doing what's recommended by going in the water together.

"This is really unusual," he said.

The fire department arrived at the north side of the reserve with a number of first responders. Sophia, 26, was unresponsive when she was pulled from the water by a first responder on a jet ski; efforts to revive her with CPR failed, the department said. Ilya was found at the bottom of the ocean about 100 to 150 yards from shore. CPR was also administered, but first responders were unable to resuscitate him as well.

The Maui County Fire Department did not immediately respond to a request for comment.