Partition Suit - Jurisdiction

Section ;-17 Civil Procedure Code ;Suits for Immovable Properties situated with in the Jurisdiction of Different Courts ;-the Suit can be filed with in the Local  Limits of any Court  with in local Limits whose  Jurisdiction any portion of the Property is situated .

Sec;- 22 ;- objections  to Jurisdiction 

Sec 22 ;- Power to Transfer the Suit

Sec 23 To What  Court Application lies/ for Transfer in case of Courts / properties are under  different  High Courts 

I need some advice on the following case for my understanding:

My Mother had purchased a flat in Mayur Vihar (MV), Delhi in 1990. The Legal Documents were made in Noida Court. The Receipt of Payment and Will by the previous owner are in the name of my mother whereas General Power of Attorney/ Special Power of Attorney are in the name of my father. My mother was 2^nd wife of my father. From the 1^st wife ; my father had two sons whereas we are 2 brothers & 2 sisters from the 2^nd wife.

My mother died in April 1993 and father died in June 2003.

My 2^nd half brother from my father’s 1^st wife has taken over our MV flat forcefully and living there. He has been claiming that father had willed the flat in his name.

Now we feel cheated as the ownership of the flat as per our understanding was always with mother as she had paid towards purchase of the property but not our father, even if the GPC/SPC are in his name. How father could make a valid will in his favour? As per your experience; do you think it will hold good and correct in the eyes of law? My half brother claims the WILL is a registered Will.

What do you advise what is technically correct? Or can you suggest a knowledgeable advocate in Tees Hazari; expert in handling these types of cases?