Is the sale of property of minor valid

Dear sir/madam Who soever it may concern Urgent and serious matter Sir may grand father aqured some land from his property and such land inherted by my forefathers threrby my grand father, one of son out of four 5sons, Got land property from his father by hindhu successio act, and threrafter my grandfather has 5 sons and 2 doughters made a unregsterd partation btween these people b/w 1969-1980/- and some major sons at that time sold there part of land and remind 2 minors held with my grand father one of the minors was my father. After some years of partation my grand father execute sale deed on bhalf of these minors on 12//02/1982, and sold the property to some personal who bought the land with the knlwelege that it was minors property and he takes some other property as surity and bought the land, My father dob 01/01/1976 my date of of birth is 17/12/1992, recently we send the notice to such person by lawer that they were replaid that it was barred by like mitation act. S