I would use transfer paper, print the wanted picture onto it and iron it onto the fabric the best part is if you mess up the picture you have infinite redos without any extra cost.
Acrylic may work, I've done multiple pants-painting projects before, and I love how they end up when using acrylics. A technique I've used before is spraying hair spray onto the painted area and letting it dry, just so there's a clear coat and so that the acrylic paint wont wash away when/once you've washed it.
I read that you can "set" acrylic by heating it, so after thoroughly air drying, put the article in the dryer and use the setting meant for that fabric. All the fabric paint I've seen has actually been acrylic, never seen other...
Anyone with a pet rabbit know how expensive it is to take care of one? I h...