What are alternatives to calcium and vitamin D if my child is lactose intolerant?

You mentioned that you have an 18 month old who is lactose intolerant. It sounds like it's actually been diagnosed, and now you're just wondering what can you give your child to make sure they get enough vitamin D and calcium. This is a really good question. Actually, a lot of kids who are lactose intolerant can tolerate a small amount of dairy product, so some can even have 1 to 2 glasses of milk a day. If your child can't tolerate any milk, but does tolerate some dairy products like you mentioned - yogurt, cheeses, ice cream - that sort of thing, then introduce that into your child's diet at least daily, as long as they're doing okay with it. Another option is a lactase enzyme. If your child is going to be drinking milk, you can give them the enzyme that they're missing, and that will help them digest the milk, and it will prevent complications like bloating, gas, diarrhea, all of those things that are associated with lactose intolerance.