Who owns the land?

this problem is not mine but of my grandfather's. my grandfather's parents gave each of every child equal division of properties before they died. my grandfather was in his early 20s when he got his property pawned to his older sister in exchange for a 2 years (Php 50.00 per month this was in early 70s) financial assistance for his studies. all of the products obtained from the farm land basically went to his older sister. after 2 years, that farm land was then again pawned to his older brother for only Php 2,000.00 good for 2 years including all the products obtained from the farm. it so happened that my grandfather's older brother deceived him. the 2-year contract continued for another year which made my grandfather indebted for another thousand pesos. later on, we just learned that the older brother takes a hold of a "deed of sale" from my grand father without even remembering that he ever sold his property. is there any way that we can take a hold of the said property? is my grandfather still the legal owner of the farm land? is there any law that we can take a hold with as protection? enlightenment please. thank you and more power.

Some are unclear.
1, Mainly. What do DOCUMENTS SHOW? = What can be PROVEN?
2. Is the dept paid back? In any case the land can't just be taken without a legal process.
3. So - is the land foreclosed? (The foreclosure PROCESSED? )
4. IF it's foreclosed - how long time ago was it? (If I have understood the law corect. Not sure if there are any exceptions.) Even IF the foreclosure process is DONE, the earlier owner (=your grandfather) has ONE YEAR to GET IT BACK.
5. And perhaps most important. Is the land TITLED? If it isn't, then it CAN'T even BE collateral for ANY loan, so if it isn't titlled it CAN'T be foreclosured...

Some SIMPLIFIED legal processes are handled by the BARANGGAY. You can CHECK with them, if they can - or have allready - decided anything concerning this land.