Ok so with so many info out there.... some don't start solids until 6 months some its better to start at 4 months to even the bf exclusively until 7 months cos of the iron intake. What is the right thing to do? I feel like ds is ready for solids but I don't want to disadvantage him. He turns 4 months next week. If I give him 2 tsp of smashed banana is that suppose to replace the milk for that feed or is that on top of the milk?