"Can you smile for me, Pinkie? A real smile. From inside, like you said. Not smiling at me. Smiling for me, smiling because I can't." I didn't want her to, I didn't care, but I couldn't. Just because you don't care doesn't mean it doesn't matter.
"I don't know," she said in a small voice. "Smiling because you can't smile doesn't make me want to smile."
"Don't smile over me not being able to smile," I told her. "Smile the smile I should have because I got to meet you. Smile the way I should have smiled when I met your friends. Laugh for me at the idea of having my own sunrise."
"Those are your smiles," she said. "It's sad you don't get to have them."
"Then smile with the smiles I should have," I told her. "Smile because it's all going to be okay."
She sniffled and looked up to me. "Pinkie Promise?"
I ran my fingers through her mane. "I Gus Promise. Cross two worlds and all the rest, this'll turn out for the best."
I don't know where that came from.
She turned and sat up in my lap and hugged around my neck very hard. "Nopony ever got that," she breathed, and then she started to laugh and cry at the same time. I hugged her back until she fell asleep holding me.
http://www.fimfiction.net/story/115322/8/xenophilia-advanced/chapter-8-waving