Babies and fish

I just read an article by Dr. Sears that babies over 6 months old should have fish (with the exception of shellfish) as part of their diet. I never did this with Lamb 1 or 2 until they were over one year old. The other night we fed tuna to Lamb 3 and he loved it. We eat a lot of fish, especially canned tuna. I think we're going to try to eat more canned salmon and feed it to Lamb 3 too.