Supreme Court Justice Samuel Alito fell ill at an event in Philadelphia last month and was treated for dehydration before returning home to suburban Washington, the court’s spokeswoman said Friday.

Alito’s illness did not require an overnight hospital stay and he was back on the bench the following Monday, spokeswoman Patricia McCabe said in a statement.

Alito was an active questioner during arguments that day in an important case about mailed ballots and participated in all the court’s hearings over the ensuing two weeks.

Alito, who turned 76 on Wednesday, is the second-oldest member of the court, after 77-year-old Justice Clarence Thomas.

The episode was first reported by CNN, which also said the treatment was administered at a Philadelphia hospital. The court did not say where Alito had been taken.