You shouldn't push someone to eat something they're allergic to.
Gerald is planning a birthday party for his son.
Gerald wants his son to have a delicious cake.
Gerald bakes a lemon cake which is not as good as his chocolate walnut cake.
Gerald bakes his famous chocolate walnut cake even though his son is allergic to walnuts.
Gerald's son and the rest of the partygoers are all able to enjoy the cake.
Gerald's son has an allergic reaction and has to go to the hospital.