If an actress plays a hero's sister role in a film.. there is no rule that she should do similar roles in future. Yesteryear heroine Sridevi acted as a granddaughter of NTR in the earlier days of her career.. but the same Sridevi romanced NTR in several superhit films later. If someone feels that it is an old reference, we can take the reference of Fatima Sana Shaikh. Fatima played Aamir Khan's daughter role in 'Dangal'.. she is Aamir's heroine in upcoming film 'Thugs of Hindostan' now.
But popular Telugu TV anchor Sreemukhi is reacting in a contrasting manner. It is known that Sreemukhi played the role of Allu Arjun's sister in 'Julayi'. There is no need for her to feel that Stylish Star is her brother even now. She has recently shared a photograph with Allu Arjun and tweeted that "Met my Julayi brother @alluarjun after ages!"
We can say that it is a risk calling a star hero as a brother. Usually, actresses refrain themselves calling heroes as brothers because they may miss the opportunity of pairing with them in future. It seems Sreemukhi is not much worried about such things.