Hi! What’s his name? It can be hard to tell whether a bun is the proper weight without knowing breed or age, but a couple tricks are 1) if when he is laying down he looks pear-shaped from above he is a good weight, but if he looks round like a circle he’s probably overweight, and 2) if you notice his cecotropes getting stuck to his bum all the time then he is probably overweight because he might not be able to reach his bum to eat them.
Luna doesn’t really play with her toys either unless she’s in the mood – she’s more of a runner and cardboard box chewer. Buns are crepuscular (most active around dawn and dusk), so he might not be as playful during his sleepy hours. That’s a good sign that he is wanting to be near you and climbing in your lap. For additional bonding, just keep spending as much time as you can with him. It doesn’t have to be physical contact – merely sitting by his cage or talking to him will help
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