inheritance

I live in Sydney. I have two brothers Imran and Khalid who live in Dubai.
I have a sister Nasreen who lives in Karachi Gulshn-e-Iqbal.
I have a brother Amjad and sister Rizwana who live in North Naziamabad.
My question is about the property in North Nazim abad where my brother Amjad and sister Rizwana live.

My sister (Nasreen) sued her one sister (Rizwana) and three brothers (Amjad, Imran, Khalid) for not selling their house in North Nazim abad and sharing the inheritance after the death of their father.
I live in Sydney gave power of attorney to my sister Nasreen to sue Rizwana, Amjad, Imran and Khalid.

So now the case is Nasreen AND Razia vs Rizwana, Amjad, Imran,Khalid
During the court case it was revealed that Imran and Khalid do not live in the sued property in North Nazimabad And they live in Dubai. Both of my brother who are living in Dubai also want Rizwana and Amjad to vacate the North Nazimabad property and share the inheritance . Both Imran and Khalid revealed in the court that they were wrongly sued . My question is
Is it possible for Imran and Khalid from Dubai to give their power of attorney to Nasreen in Karachi (Like I did from Sydney ) to sue Amjad and Rizwana (who are living in the property and are not selling it). At the moment both Imran and Khalid are defendants.
Can these defendants turn into plaintiff with us (i.e. Nasreen and Razia) to sue Rizwana and Amjad in the same court case ? Please let me know