“It’s going to be alright, sir,” Harry said over and over again, more worried by Dumbledore’s silence than he had been by his weakened voice. “We’re nearly there. . . . I can Apparate us both back. . . . Don’t worry. . . .”
“I am not worried, Harry,” said Dumbledore, his voice a little stronger despite the freezing water. “I am with you.”

Harry Potter and the Half-Blood Prince – J.K. Rowling