LYNN – His face is the picture of boyish glee beaming down on Wyoma Square, a reminder that the search for five year-old Giovanni Gonzalez is entering its fourth month.The East Boston kindergartener has not been seen since his father’s neighbors saw him playing outside 2 Brightwood Terrace on Aug. 16. His mother went to pick him up at Ernesto Gonzalez’ apartment a day later and summoned police after she could not locate her son.Ernesto Gonzalez told police he never saw the boy that weekend and, according to the District Attorney’s office, he has not discussed the boy’s whereabouts or fate since Aug. 17.”It’s a gut-wrenching case,” said Michael MacDonald, a Lynn attorney all too familiar with missing children cases.He represented Magdalena Rodriguez, the mother of Jesus De La Cruz, who vanished from Park Street on Sept. 28, 1996. MacDonald said Gonzalez’ disappearance and his father’s silence remain conversation topics in Lynn District Court.”This is a little boy; he’s the father. You hope he would do anything to help the boy. That’s the moral issue. The legal issue is quite different,” MacDonald said.He said Ernesto Gonzalez’ refusal to speak to authorities from his cell in the Essex House of Correction reflects the wishes of “any good defense attorney” to protect his client.Another local attorney, Eric Jarosz, said the caliber of the two attorneys on opposing sides of the Gonzalez case underscores its seriousness. Top public defender Lawrence Maguire represents Gonzalez and prosecutor John Dawley has appeared for District Attorney Jonathan Blodgett on hearings involving Gonzalez.Gonzalez pleaded innocent to a child endangerment charge on Aug. 18 and is due back in court on Nov. 18. Maguire declined to comment on the case Thursday.Police, the DA’s office and the Center for Missing and Exploited Children remain determined to find the boy.Days after his disappearance, the Center posted appeals for help finding him in Massachusetts and Puerto Rico. The boy’s mother told police on Aug. 17 that Giovanni wanted to visit a half brother on the island.”That’s our focus still,” said Center senior case manager Gary Gardiner earlier this month.Police searches in Puerto Rico have not produced leads to date but police have not abandoned search plans there or locally.”We ask anyone with any information to contact Lynn police and help us bring Giovanni home,” DA’s spokesman Steve O’Connell said.Daisy Colon also remains committed to finding her son.”I don’t let negative thoughts come to mind. I just try to stay positive.”