Unfair coworker

So currently I work as a CNA. Anyone that is a CNA knows that the work should be equal. Well... there are three hallways at the facility I work at. I work in the rehab hall along with another male coworker (I’m 23 he’s 32). He constantly disappears and if a call light comes on, I have to attend it. It’s hard work and he doesn’t help at all. We’re obligated to take a 15 minute break and he takes a 20 min break when I don’t get one at all because we’re always so busy. He disappears to the shower room and if a call light comes on he’ll stay in there.

How do I get him to share the work? I’m not the type of person to lash out or even tell him anything.