I use vitamin C tabs that are flavored for different fruits not just citrus. I believe it is halls that makes them. Sunkist also makes chewies form strawberries that have a lot of vitamin C.
If she doesn't want to take tablets and doesn't like oranges go with just straight Strawberries, Kale, bell peppers, broccoli, papaya, cauliflower, pineapple, brussel sprouts, kiwi, and mango all have more Vitamin C per a serving then Oranges do. It is kind of fascinating that oranges is what we are all taught where there are so many other options to add to the diet for vitamin C.