Donald Trump and Jeb Bush repeatedly traded blows on Saturday night in what proved to be the most aggressive Republican presidential debate yet. Trump blasted Bush’s national security plans, then went on to slam his brother George W. Bush. “The World Trade Center came down during your brother’s reign, remember that,” he declared amid boos from the audience. Bush was quick to fight back and announced that he was “sick and tired” of Trump going after his family. Meanwhile, Marco Rubio and Ted Cruz clashed on immigration. Rubio took a jab at Cruz for not speaking Spanish, which prompted Cruz to rattle off some Spanish. The one thing that all six candidates did seem to agree on during the debate was that the Senate should try to block any nomination by President Barack Obama to replace the late Justice Antonin Scalia, who died over the weekend.