Victoria Gayle, who covered up the death of her baby son for 11 years until it was found in a garden shed in west Hendon, has been sentenced to 21 months in prison.
There was no reaction from the 32-year-old as she stood in the dock at Kingston Crown Court.
Gayle, of no fixed address, had previously pleaded guilty to preventing a lawful burial, but pleaded not guilty to perjury and perverting the course of justice. The allegations will lie on file.
Judge Susan Tapping told Gayle: "Your little boy was denied a decent burial.
"A web of lies began in 2014 and went on to every authority that tried to find out what had happened to him.
"The full truth of his sad and short life will never be known."
Despite two post mortems and the long-term deterioration of her son Kyzer's remains, the cause of his death has been given as "unascertained".
Gayle was sentenced to 21 months and will remain on licence for 12 months on release.
Estimates suggest that Kyzer may have been around 13 or 14 months old when he died, and little is known about him since he was last seen in 2004.
His remains, showing he was malnourished, were found in a garden shed on May 31, 2016.
This was at the west Hendon home of Gayle's mother and step-father, but they knew nothing about the death.