So thisgt high chair is perfect. It wheels all around. He can sit up in it. The harness is secure enough that I can turn my back and trust that he's OK. Plus, it has a big tray that pulls right within his grasping distance. I've been putting lots of toys on the tray, and he has lots of fun grabbing all the different toys. I think Jack likes his new chair.
Here, Jack is in the chair. There is much growling, two hiccups, and one "googoo" involved: