Can anyone tell me if there is a pattern for a converse bootie?
I believe there is, or one for children that can be downsized. Have you tried googling for it (use slipper as well as bootie) or look on pattern sites such as www.knittingpatterncentral.com or www.dailyknitter.com
Most of the time you can find what you need by doing a Google search like I did.
I've used this pattern and they are adorable.