It is just a delicious drink. Set a pretty table, child size or use a TV tray with pretty placemat and napkins. Make it a special time. Maybe have more than one teaparty per day. Apricot nectar works for some people.
Prunes are also good.
Add ground flax seed to oatmeal or other cooked cereal for breakfast, does not change the taste. Purchase flax seed at health food stores, grind in blender to almost powder consistency, store in closed jar in refrigerator. Have a special time of day to sit for a while on the potty, once in the morning and again in the afternoon. Read a book, grunt with her for encouragement. Establish a habit of going to the bathroom on a scheduled basis and she just might start having BMs.