Florida's Department of Children and Families filed a report on Tuesday after the country singer took Zander from his father's house in Cape Coral, reports The AP.
While McCready has visitation rights with the child, legal custody of Zander was handed over to her mother.
McCready's publicist said in a statement Wednesday: "The 5-year-old boy has been with his mother for more than 30 days. Law enforcement officials spoke with the child and saw Zander via Skype yesterday."
She is said to have been given until Thursday by law enforcement officials to return Zander to his father's home.
McCready has denied accusations that she is guilty of kidnapping her child, telling Access Hollywood: "I am working with lawyers to try to get all this straightened out.
"I did not steal my child, as it would be impossible for me to kidnap what already belongs to me! There never was any missing persons report and never an Amber Alert."
In May 2010, McCready was hospitalised after overdosing on prescription medication in what was thought to be a suicide attempt.