My husband had a neobladder in October. He is generally continent during the day but continues to have problems at night, especailly following chemo treatments. Because he no longer has the sensation that the bladder is full, he empties it on timed scheduled. For months he set an alarm to go off every 2 hours during the night. Needless to say neither one of use got a decent night's sleep.
Sleep deprivation encouraged me to take on an exhaustive search of incontinence products. The solution we found is by a company called Alphadry. The device's top looks and functions much like a condom that is attached to a small bag that prevents the backflow of urine. The company advertises that a similar product is used by the astronauts while in space. It has been a godsend. Our bed remains dry and he is now able to sleep through the night.
Good luck to your brother.