The Cook County Medical Examiner's Office identified the two as Jream Jaycee Washington, a 1-year-old girl, and Wyatt Bryden Patton, a 6-year-old boy.
The medical examiner's office listed the manner of death as "pending" for both of the Matteson children.
Chicago police believe the deaths of the two kids and a 31-year-old woman are connected and possibly stemmed from a domestic dispute.
Washington was found in the water around 11:23 a.m. Saturday in the 5700-block of South DuSable Lake Shore Drive near 57th Street Beach. She was pronounced dead at the scene.
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Later in the day, crews found the bodies of Patton and the woman in the water around 2:23 p.m. in the 6300-block of South Hayes Drive near 63rd Street Beach. Both were pronounced dead at the scene.
The woman's identity has not yet been released.
Officials did not immediately provide further information.
The video in the player above is from a previous report.
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