legality of donation of real property

Hingi lang po ng advice. This is the case, yung lolo ko nagbigay ng lupa sa friend niya, yung apo ng friend ng lolo ko is still claiming another area kasi kulang daw yung lupa na napunta sa kanila sa kung ano ang totoong ibinigay. My lolo and his friend are already dead so di na sila pwede magtestify na tama yung ibinigay sa kanila. Ang area ng lupa which belongs to us is 11,000 square meters but then nung nagapply ang father ko ng title only 9,400 was approved kaya yung difference nung 11,000 and 9,400 is beiong claimed nung apo ng friend ng lolo ko. Case is still on going and there is no resolution yet. Ang iniisip ko is pwede gawing defense yung legality ng donation. I dont think all of the legal matters to make the donation valid was complied before. What can we do para di makuha sa amin yung lupa. Anyway, the land involved is a beach resort kaya ganun ang interest nila sa lupa. Thank you!

ws the donation made in a notarized document? is there a tct covering the property?