Dairy Free PB and Banana smoothies

Got a picky eater?  If you have a kid with Autism or SPD I'm sure you do!  My youngest little dude who has speech and sensory problems has been getting pickier by the day and isn't gaining weight.  Now there was a simple solution when my daughter went through this at the same age--Pediasure--a meal-replacement shake for toddlers.  We also used Carnation instant breakfast added to whole milk.  Now here's the problem, my youngest is severely lactose intolerant to the point where he can't have any bit of milk product or cross-contaminated stuff.  Even though pediasure is lactose-free, it has whey in it which is a milk bi-product that he reacts to and Carnation has powdered milk in it.  So what to do when he has days of literally eating nothing?  Well, I came up with the idea of making soy smoothies.  So yesterday, I got out the blender and threw in a banana, a cup of soy milk and two tablespoons of peanut butter.  It made about two toddler servings.  He loved it, so today I added a very small amount of carrots and I hope to increase the veggie amount and vary the fruit over time.   I tasted it and didn't notice a difference with the carrots.  Awesome idea for picky eaters.  Now mind you, we did try this for my daughter and the thick texture totally turned her off, but little guy loved it and bonus is it has far fewer preservatives than pediasure anyway.