Kyron Horman was 7 on June 4, 2010. His stepmother, Terri Horman, told authorities she last saw him walking toward his classroom.
A massive search came up empty. No arrests have been made.
In a settlement signed Tuesday, his father, Kaine Horman, got custody of 5-year-old Kiara Horman, the daughter he had with Terri Horman.
The couple divorced after Kyron disappeared. The settlement allows Terri Horman eventual visits with the daughter.
Desiree Young, Kyron's biological mother and Kaine Horman's first wife, said in a Facebook message Wednesday that a private search will be conducted June 20, 21 and 22.