C.H.
We had the same problem around that time. Our Dr. told us to give our son a little prune juice (warmed up). We did 2 oz. with 2 oz. of water. At first we were trying it once a day and then eventually went to 2x per day for awhile. I would cut back on the rice cereal as all the iron is what most likely constipates them and gives them such hard stools. Also, a warm bath tends to help it come out. Hang in there. Now that my son is 8 months+ and eating other solids (fruits that start with "P" especially) we don't have to do the prune juice at all anymore. You can also try switching to oatmeal since it's less constipating. Our son used to scream when he would go and it was very hard and uncomfortable. Good luck!