Upvote:4
The visa application also has a space to indicate that someone else is paying for the cost of your trip. The forms for your wife and child should indicate that you are paying for the cost of the trip. They can answer zero to the questions about how much they are personally spending, and also their income and expenses (assuming they actually have no income). You should include the expenses for them in the question about the amount you are paying, and also the question about money you spend supporting them in your regular expenses. You should note on the applications that you are traveling together.