James didn't need to see it to agree. Love, and every other emotion, were incredibly important; he didn't want to feel nothing. And he was very grateful that his family in that world had escaped such a fate, although the things Harry had said made him worry quite a bit about his son's future there. Even though that Harry was here now, his life was still continuing back in his world, and-- well, there was nothing he could do about that. But there might be something he could do for the Sirius standing in front of him right now.
His heart ached when Sirius said he missed him; James knew the feeling of missing his best friend all too well. His hand was still lightly on Sirius's arm, but he took hold of it properly, and stepped closer, reassuring him through physical contact. He was more than willing to be hugged and cried on, but if Sirius needed to get through the talking part first, he didn't want to interrupt.
"There's more for you here," James said. "I get that." Even if his own James wasn't here, he had a James. James remembered his own elation at seeing Sirius here for the first time, even though he was from a different world. "Maybe he just needs there to be more here for him, yeah? You'll have each other either way, so there needs to be something else for him, too."
He gave a slight smile. "They should put him in that room with all the other Moonys. I'm pretty sure all they do all day is read and eat chocolate, except when my hubby gives dance lessons or turns on Dirty Dancing."