The Doctor's eyes shot open, and he looked around. He saw Jack lying next to him, asleep, and he quickly wrapped his arms around the other.
"Doctor? What's wrong?" Jack asked sleepily. "You're shaking." He said, growing concerned.
"I'm sorry. I didn't mean to wake you up." He mumbled, against Jack's chest.
Jack ran a hand through the Doctor's hair, trying to calm him down, when he felt the Doctor's warm tears on him. "It's alright. I don't mind." He pulled the other man closer. "Now tell me what's wrong."
"It's nothing. Just a bad dream. You don't have to worry about." He said.
"Well I am worried about it. Tell me what happened." He said, still running his hand through the Doctor's hair.
"You died in it. And you didn't come back." The tears where coming faster now.
"It's okay. I'm here Doctor. I'm here and I'm perfectly fine, and alive." He said reassuringly, placing a light kiss to the Doctor's head.
Eventually the Doctor calmed down enough that he managed to fall back asleep, in Jack's arms.
Jack moved one arm to try and wipe away the Doctor's tears, but the Doctor clung to him tighter making a small sound of protest, so he just kissed him on the cheek and wrapped his arm back around the Doctor.
He noted the small smile on the Doctor's face when Jack wrapped his arm around him again, and smiled back even though the Doctor couldn't see it.
He knew he wouldn't get back to sleep now, that he would stay up and make sure the Doctor didn't have another nightmare, but he was okay with that, because he was holding the Doctor in his arms.