Can you drink dark coloured drinks with Duplex Kidneys?

[CharlieA123]

Iv recently met my step daughter who has been diagnosed with Duplex Kidneys.However with her mum not being very supportive toward myself or dad who has recently just been having contact (long story for another day) all information we have recieved has been from my 9yo step daughter who is under the impression she is not allowed any dark coloured drinks, i have looked on line but havnt found any information. So my question is with Duplex Kidneys do you have to watch what you eat and drink?