A Methuen couple is raising questions about school safety plans for their son, who is allergic to nuts, after he was sent to the hospital on June 5 for treatment after a severe reaction. It was the seventh such hospital visit since Carl Sackrison, 9, first entered Methuen schools several years ago; he just completed fourth grade at Marsh Grammar School and previously attended Tenney Grammar School. Sackrison's parents said that while a specific health plan was put in place to keep their son's classroom nut-free, he has been exposed to products with nut warnings, one of which caused his most recent reaction. His parents also said he has been bullied by other children who deliberately exposed him to nut products in the classroom.