A judge decided today that the Bronx father charged with murdering his 5-year-old son will not testify to a grand jury.

Police say Leonardo Espinal fed his son Stewart Espinal pizza laced with rat poison. The boy was found dead in a bathtub last week. His sister was also poisoned, but survived.

Espinal's relatives say he admitted to poisoning his son, but didn't try to drown him. His son and daughter-in-law, who were in court today, say Espinal was depressed because his wife was allegedly having an affair.

Espinal is due back in court in January.

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