Hii! Sorry for the late reply!

"Ah-ti" and "Ah-Xiao" are a very intimate/delicate way of calling each other out. I did a bit of research and consulted some Chinese speaking acquaintances so they could explain to me how it worked. The "ah" in front is an intimate and cute way of calling out another person's name. And it is only used when you are very close to that person!

I hope it can help 💖🤗