More often than not, the CP patient is also immature in nature, they have a tendency to be more childlike in some of their behavior, so you may need to look at getting her a device based on that. This also explains why she may be rather picky or selective as well. She may latch on to the first thing that attracts her and will not let go of it, figuratively speaking.
In any normal situation I too would suggest the Nautilus, but they are prone to having a tight fit, even I have to use a towel on the base to remove for a coil change or refill, not to mention the coil can remain in the chimney when taken apart, neither of these traits would be a good choice for a CP patient. I am certain she has some diminished motor skills in her hands, even if to a small extent.
OTOH if you could rebuild an Atlantis coil to above 1.6 that might work well. The Atlantis are easily taken apart(the base) and the AFC can be set to the smallest port and using a smaller diameter drip tip it could be very close to a tootle puffer tank. And they also have the SS cage around the Pyrex to keep it safe for her.