( CNN ) -- It 's been 31 years since Stanley Guidroz first reported his 3-year-old son missing in Tacoma , Washington . Investigators , after reopening the cold case , now say the boy , Wallace Guidroz , was never missing at all and that his father had killed him . Guidroz , 57 , has been charged with first-degree manslaughter after he confessed to the crime , said Pierce County Prosecutor Mark Lindquist on Tuesday . `` This is another success for the Cold Case Unit , '' said Lindquist . `` Justice matters , no matter how long it takes . '' Guidroz first reported his son missing in January 1983 , telling Tacoma police that his son had gone missing in a neighborhood park after they had gone fishing together . Guidroz said he believed that a family they had met in the park had kidnapped him , prosecutors said . Police were unable to locate a family that fit the description Guidroz gave them , and they were unable to connect Guidroz to the boy 's disappearance . For years , the mystery of what happened to Wallace remained unsolved . Guidroz left Washington state in 1984 and did not return , according to a press release from the Pierce County Prosecutor 's Office . In 2011 , Cold Case Unit Detective Gene Miller reopened the case . Miller reviewed old documents from the initial investigation and saw that Guidroz 's stories never seemed to add up . There were `` several inconsistencies in Guidroz 's account of the events from the day Wallace went missing , '' the release said . Guidroz resurfaced in Louisiana in March 2011 after reports that he had been charged in the killing of his wife , who is not the mother of Wallace . Guidroz was convicted of fatally stabbing his wife multiple times after they had gotten into an argument . He drove around aimlessly with her body in the back of his car before driving to a nearby police station and confessing to the murder , according to CNN affiliate WWL . Miller traveled to Louisiana to question Guidroz about Wallace 's disappearance . Though Guidroz initially provided several more versions of his original story , he reportedly admitted to killing his son . Guidroz said he and Wallace returned home after going fishing , but that he `` lost it '' after Wallace began fussing in his high chair . Guidroz said he hit the toddler , which caused the boy to fall to the floor and hit his head . Wallace was n't responsive after the fall and Guidroz told Miller that he `` knew he was dead '' but that he was afraid of being labeled a `` child killer '' in prison . Guidroz buried Wallace near the Tacoma waterfront and then called police to report him missing , prosecutors said . Guidroz is currently being held in a Louisiana prison for his wife 's murder . A warrant has been issued for Guidroz to return to Washington state , prosecutors say . It is unclear whether Guidroz has retained an attorney . NY businesswoman accused of killing autistic son . Dad accused of slaying five kids .
Stanley Smith has been charged with murdering his 3-year - old son . Police believe Guidroz confessed after detectives interviewed him in Florida . A warrant has been issued for Guidroz to return to Washington .