How does Russ eat and drink? I mean the mechanical details. Can he move his tongue and jaws? Can he close his mouth?
Has he ever used a drinking straw? Was he able to drink from a bottle as an infant?
Clearly, this is all very disgusting, but I'm just curious how he managed to stay alive as long as he has.
He can move his tongue and jaw, but not as effectively or with as much precision as someone whose cranial nerves are intact. He has similar difficulty controlling his larynx and throat muscles in general, but they're not completely paralyzed (he can swallow, for example). He can't move his lips or cheeks to create suction. Historically, most Moebius babies died in infancy because they're unable to nurse. Russ required a feeding tube at one point, and you can see the scar in photos where he's traumatized us by appearing topless. He can't move his facial muscles or move his eyes from side to side. Often, when Moebius sufferers blink or try to close their eyes, their eyes don't close all the way. Russ has mentioned using a sleep mask, so this would seem to be the case for him.
Russ has exhibited a fondness for softer foods, as well as extremely sweet and sugary ones, possibly due to his difficulty eating and tasting, and possibly due to comorbid autism. He eats by spooning or pouring/sliding food into his mouth, chewing as best he can, and swallowing, though since he can't close his lips the whole ordeal is not pretty; he regularly drools even when he's not eating. Moebius sufferers also frequently have problems with the formation of their palate, making speech and eating even more difficult. It's unclear if Russ has a deformed palate.
Moebius is loosely associated with a lower IQ and a higher incidence of autism (by some estimates up to 40% of children with Moebius have some degree of autism) but it's worth noting that the majority of sufferers are neurologically and intellectually normal. Russ has a lot of mental problems, but not all of them can be blamed on Moebius (or at least, not directly). It's also associated with hearing problems (Russ has never indicated he has hearing problems, he's just naturally a shitty songwriter) stunted development and/or webbing of the fingers and toes (Russ does have weird stumpy fingers, though he's not actually missing a joint as is commonly perceived) and underdeveloped or completely undeveloped muscles in the chest and shoulders (pectoral and trapezius muscles) which Russ absolutely displays. Delayed puberty, genital abnormalities (such as micropenis and hypospadias) are also statistically more common in Moebius sufferers than in the general population. Russ also appears to have significant bowing of his legs and something weird about his gait, which is also likely to be related to his condition. There's some dispute over how tall he is, with estimates in this thread (some of which come from people who have encountered him irl) range from 5'3" to 5'7" or 5'8". For what it's worth, he claims to be 5'8". It's unclear if he's naturally this size or if his limbs are stunted; he does appear in some pictures to have a disproportionately long torso, but it's very hard to say.
He has stayed alive through the marvels of modern medicine and the determination of his adopted family, who gave him the best life they could, including extensive speech therapy, extra-curricular activities such as piano lessons, and even expensive surgeries to attempt to transplant muscle from his thigh to his face to give him some ability to stop drooling (it didn't take).