Welcome to YT! We had to purchase Katie Scarlett a step in cat harness at Petco when she first came home. It was the only one that fit. She was 2.8 pounds at the time. She has grown into a more proper step in one now though. We've only had her 2 months and have already purchased 2, so I figure as she grows and the others wear out, buying more is inevitable. So I would purchase one that fits her the best now and get her used to the harness. I've heard lots of good things about that Puppia harness here, but the one we have is a padded one from Petco. Katie Scarlett loves it. Even the XS was big on her at first though. Good luck!
