Jonah was admitted with a bad stomach ache and Lisa Cuddy assigned him to Eric Foreman because he wanted more responsibility. Evan and Melinda were always at Jonah's side. Foreman was surprised how well the two brothers got along, particularly compared to his relationship with his own brother.
However as Jonah grew worse and House refused to help, Foreman was speaking with Chase and Cameron, who were helping out. Chase wondered if Evan might be envious of Jonah and had poisoned him. Foreman immediately rejected the suggestion, saying if anything that Evan was always looking out for Jonah. All of a sudden, Foreman remembered the remark about vitamins and rushed out of the room.
He started treating Jonah for iron toxicity from vitamin pills. His mother was confused because she only gave him one a day, but Foreman had realized that Evan had been giving Jonah more vitamins in an attempt to make him stronger. Evan admitted what he had done and realized that's why Jonah was sick. He was worried Jonah would hate him, but Foreman reassured him.
As it turned out, Jonah recovered quickly and the two brothers left the hospital together.