A. Since property nature is ancestral, X's minor children have right to challenge the property transaction within 3 years from the date attains majority.
B. If minor property wants to transfer that the Court permission is required, but some exceptional cases the Court upheld the transaction made by the natural guardian(i.e, father) in the absence of Court Permission for the legal necessity or benefit of the children.
C. In case X inherited the property under Section 8 of the Hindu Succession Act, 1956 other than ancestral property ( even though property earned by the grandfather and the absence of 4 generations), then only minor children have no right to question the same because of this property is called individual property. In your case, minor interest unequivocally established.
D. Therefore, I hereby suggesting you to approach expert advocate to analyze the minimum 42 years land records with respect to the same.