Can I be disciplined by my employer for being sick?

Question Details: I work in the state of Texas. I heard a rumor that if anyone is sick 5 times in a year that they will recieve a oral discipline from their supervisor and on the 6th a written. Our policy states that if we are sick more than 3 days that our superviso may ask for a doctors excuse but this has rarely happened and has never been a inforced policy. Can my employer discipline me for being sick? Can they terminate for being sick? Can my supervisor even ask me what my sickness was when i return? This is coming from the Dept. managers and not the Human Resource Dept. Important Notice