A California man pleaded guilty Tuesday to killing his 5-year-old son after a family trip to Disneyland set off a two-month search for the boy’s body.

Prosecutors say Aramazd Andressian Sr., 35, killed his son, Aramazd Andressian Jr., to get back at his estranged wife Ana Estevez while they were going through a divorce.

After investigators repeatedly combed the area surrounding Lake Cachuma in Santa Barbara County, they found the boy’s remains on June 30. It remains unclear how he was killed or what evidence linked the father to his death.

Andressian Sr. made national headlines in June when he cracked a joke during his extradition hearing. A police officer also said his behavior was inconsistent with that of a grieving parent.

On Tuesday, Estevez was surrounded by sobbing family members as she wept in the front row of the courtroom while holding the urn with her son’s ashes.

Andressian Sr., who wore yellow jail scrubs, entered the plea to first-degree murder in Los Angeles County Superior Court in Alhambra.

He previously pleaded not guilty to a murder charge and was being held on $10 million bail.

Los Angeles County sheriff’s investigators believe the boy was killed in the six-and-a-half hours after he left Disneyland and headed to Lake Cachuma about 150 miles away with his father on April 21.

When Andressian Sr. failed to hand the boy over during a planned custody exchange on April 22, Estevez reported her son missing.

Officials believe the 35-year-old had attempted suicide after he was found alone the following day in Arroyo Seco Park, passed out from prescription pills in a car doused with gasoline.

While Andressian Sr. was unable to account for his son’s whereabouts, investigators believe the murder was ‘pre-planned’ and motivated by the divorce from Estevez.

Investigators searched the area surrounding Lake Cachuma several times before the boy’s remains were finally discovered on June 30.