Before help arrived, James R. Jenkins, 30, jumped into the water in an attempt to save Walker.
Jenkins was able to reach the child, according to police. Other bystanders, police officers, and Columbus Division of Fire personnel made several attempts to rescue the pair.
Jenkins and the child went under the water before they were able to reach the shore.
Rescue divers were able to pull both Jenkins and Walker from the water.
Jenkins was transported to Grant Medical Center, where he later died.
Now Walker's family and Jenkins' family have filed separate lawsuits alleging wrongful death. In the suits, lawyers say Hartford on the Lake Apartments marketed its pond as recreational but failed to provide safety measures and rules to protect residents.
The lawsuit also says Walker and Jenkins are not the first to have died as a result of lack of safety at the pond, citing the deaths of Shennell Mallory, 24, and her daughter, Kamya Preyor-Pettiford, 4, who were killed when a vehicle crashed into the same retention pond Feb. 27, 2011.
NBC4 reached out to the apartment complex for a comment on the lawsuits but did not receive a response.