You may find that the inability to walk much or get in and out of bed is a sporadic problem.
Sometimes my husband is unable to sit up in order to get out of bed, sometimes he sits on the side of the bed but has forgotten how to stand up. I have days when he can barely walk a few metres and days when he seems to recover and can walk a fair distance (even though quite slowly).
Some days he sits or stands upright and other days he leans precariously to one side and is at risk of falling.
He also has sporadic problems when either sitting down on the loo or trying to get off it.
I do understand your concern, particularly overnight. I have to rush to be at my husband's side should he need to get up because he can be quite disoriented when waking up - and also quite wobbly on his feet (if he manages to stand).
There's never a day or night the same it seems