Sleep Apnea Treatment

My mom may have a sleep disorder and we do not know what it is. She falls to sleep very easy, all she has to do is lay down. Half the time she is not even tired. Then when morning comes she has trouble waking up. Someone has to call her in order for her to wake up all the way or she will fall back to sleep. She is not having irregular dreams or breathing patterns, but I am very concerned about her.