Sister - sleep disorder problem - Please HELP !

My sister is in her late 40's

She seems to have a sleep problem.
This has been going on for years. She can fall asleep ok but she is up
anywhere from 2 am thru 5 am.
Besides she is a very light sleeper.

Even with sleeping tabs she does not get a full nights sleep.

No major health problems.

She is so frustrated with this problem.

What could she do ?

Any good sites ? Any really good book ? or tapes on this ?

Is this common ?
Is this curable ?

Has anyone been cured of this ?  anything that worked ?

Pls HELP !

Anna