The SPD Blogger Network has many, many blogs about SPD children with eating issues. One of my sons, now an adult, was a very picky eater when he was a child. There were maybe 5 foods he liked. For a while I tried making up a kids menu and before shopping I'd let him pick some meals for the week. When he became a teenager, it became increasingly difficult to get him to eat breakfast or lunch. The only thing he would agree to "eat" was a Slim Fast shake. Many people told me how terrible it was that I was letting a skinny kid drink a Slim Fast shake, but my motto was something is better than nothing. Smoothies are an excellent source of nutrition for picky eaters, and there are hundreds of recipes on the net. If you can find a smoothie or milkshake recipe he likes, add a little pea protein powder to it (I buy mine at IHerb.com). Start with a very small amount (1/2 tsp), and if he tolerates it a couple times, try a teaspoon, and so on. My daughter who has SPD, but does not have eating issues, tolerates a 4 oz. smoothie with a tablespoon of pea protein powder. Any more than that and she says it tastes funny. We also add a little to Kraft Mac & Cheese to up the protein.