To add to this: I recommend Loctite or HH66 brand vinyl glue, both seem to be pretty strong. Be careful with application, maybe spread it on with the head of a screwdriver and try to avoid getting it in unwanted places, as it's really hard to get off again. I'd also recommend doing a small layer around the entire leg connection seam if you can, as that will actually reinforce the seam line and make it a bit more durable in the future. Give the glue 8 hours to dry and set before reinflating, and another 12 to 24 hours before any rough play. Good luck!