It's ok to start with si sen brown rice. But do note that for Moon Rabbit brand si sen brown rice, even when the box stated that it is instant i.e. just add hot water to mix, it is still better to cook it over the stove for a few minutes to get a smoother texture. If you just add hot water the texture will be very sandy and some babies who are just starting on solids may find it hard to swallow well. Also some babies may get constipated with si sen brown rice. My boy constipated badly unless I add in fruit/vege puree.