However, I draw the line at covering for them.
I'm not saying that I have never worked an extra shift on short notice, but I avoid it like the Plague. My reasoning is this: I work my schedule. I avoid calling in unless it is impossible for me to go to work. I have, more than once, called work and had them send someone to pick me up because my car has broken down. I work when I'm under the weather and injured. While I don't really expect everyone to be exactly like me, I don't expect them to call in more than ten times a year (multi-day illnesses count as one in my mind), either.
Once you say "yes", the powers that be start calling you to come in all the time. You become the "go-to girl". Pretty soon you can't count on getting a day off, ever. I don't know if this is true of every facility, but that's how it works at my workplace.
I'm not interested. I don't care if it means overtime pay. If I start doing this, I'm going to wear out and then I'm going to be the one calling in sick or injured. I'd rather be the girl that they can rely on to be in when scheduled. I draw the line at trying to be SuperAide.