You really only have two realistic options...
One gang switch by door - You could just feed both bedside switches through a one gang switch by the door though this will mean they will have to get out of bed if they have forgotton to turn it on when entering room
Two gang switch by door - just wire as normal two way circuit for each lamp (my prefered way of doing this)
There is actually a third option which would mean they can always turn the lamp on from the bedside regardless of the state of the door switch but this would involve a relay for each lamp which would be wired like a motor stop start circuit usning momentary push buttons (ie. 'stop/start' by bed and 'stop' by door)