How do you keep yourself sane and awake during the week when you have to cope with a 9 years old and a 18 years old who always fight for the remote control. 9 years apart and still fighting.

Educating the kids are important especially from young. Given their age, they should be sensible enough. You may wish to try other ways like being strict with them if you haven't. Show them yr authority as a parent. At times, you may need to use both the hard and soft approach. My suggestion is to have a heart to heart talk individually with them 1st. Understanding them is equally important.