When Junior does wake up, naturally he wants to work on putting this most exciting of new skills into practice. At this point, the thing Junior needs most is to be gently helped back into his favorite sleeping position and soothed back to sleep. You may need to do this several times a night during the phase when your child is learning a new skill. When Junior has mastered the new skill, he will resume sleeping through the night, if in the mean time he hasn't come to depend on rocking or feeding. Then it is very important to take care of his needs.
Children understand that the rules are different when they are sick.
As a parent, the challenging thing is to determine if your child is awake because of illness or sleeplessness. Over time you will become very good at sensing what is going on. I'm sure this habit, as you put it, will be hard for both of you to break. There will, most likely, be many times during the nights ahead when you will want to pick him up and rock him back to sleep. It will be much easier for both of you if you don't unless, of course, he is ill or in physical pain.