After a day out with his family at Bosworth Water Park near Leicestershire, England, five-year-old Charlie Dunn wandered away from his parents as they were packing the car to leave for home.
His body was found submerged in a lake by another boy looking for his goggles in the water.
Charlie was rushed to hospital, but died from his injuries on July 23 last year.
Now, his mother and stepfather - 28-year-old Lynsey Dunn and Paul Smith, 36 - have been charged with manslaughter by gross negligence in connection with his death, BBC reports.
Lynsey and Paul were taken into custody following Charlie's death, but were released on bail before charges against them were dropped in December.
The pair were arrested again in March, and this week, were charged in an appearance at Leicester Magistrate's Court.
The couple - who have two other children - have also been charged with seven child neglect offences.
Charlie's stepfather was also charged with two counts of witness intimidation, one count of threats to damage or destroy property by fire and eight driving offences that are alleged to have taken place in January and June of this year.
Family remember Charlie as a "very loving, always happy" little boy, who was nicknamed the 'Milkybar Kid' because of his glasses and blonde hair.
"He was brilliant at his schoolwork," Charlie's step-grandmother Sharon Robinson told the BBC at the time of his death.
"His mum has got his school report and he was outstanding on his school report.
It's a shame because he had a lot of future in front of him."
On a Facebook page dedicated to Charlie's memory, Lynsey and Paul maintained their innocence.
"Still can't believe your no longer here charlie please help me n daddy 2 get off the investigation (sic)," Lynsey wrote on June 18.
"As you kno mummy and daddy didn't do this 2 you sweetheart and please help us get your sisters nd your baby brother bk."