Nine was quietly listening, standing there, waiting. He heard those words, he understood them, he knew that Ten was right, he knew that they couldn't keep going back, that they'd snuff out all of Time and Space if they did.. but it didn't stop him from wanting it. It didn't stop him from entertaining the idea.
"We can't, Doctor." He agreed quietly, blue eyes lingering on the sign the other Time Lord was holding onto. It took a few long moments before he spoke up again. "You're right." He already knew he was right, Doctor.
"Rose and I are back on good terms." He finally changed the subject, this time with a smile settled onto his face. "She stole my jacket, you remember she's always had a thing for my jacket. Wouldn't let her get those grabby hands on that coat of yours, you might never see it again."