Smoothies yay or nay for a 16 month old?

Im in australia and its been hot hot hot here for the past week or so and my 16 month old isnt eating much so i have been making her smoothies that consist of pionate fruit frozen yoghurt, frozen raspberries, fresh strawberries and blueberries, banana and milk. My SIL tells me that they would be extremely high in sugar and probably not to good for her. whats your opinion?