DS is 5 1/2 months and I'm just starting to wean him on baby rice, carrot puree etc. Do I have to sterilse the ice cube tray, the spoon and the bowls that I put the ready puree in? Seems a bit strange when he's putting everything he can get his hands on in his mouth at the moment! Also, unrelated question but can I put sweet potato in the blender or will that make it all starchy as with normal potato meaning that I have to hand mash it? Mucho gracias!