How can a person gets adverse possession over the property

Mr.A had taken some money from Mr.B.Both relatives.ancestral agriculture property was transferred by Mr.A to Mr.B instead of money.Now this transferred to Mr. B's son through gift deed.Since the property is far Mr.A and his son had allowed Mr.A to look after property & give some return from agriculture. Now Mr. A's son has filed a case stating that 1. he was major (18yr 1month) when his father sold it to Mr. B and also wrong age is mentioned and there is a conspiracy hence sale is illegal.(But in sale agreement his father has mentioned that his son is 16yrs. The transaction b/w Mr.A and B was done more than 12yrs back and from then on Mr. A and his son are looking after the property while giving some amount to Mr. B and his son from agriculture.) 2. Since he has been looking after the prop for long he pleads the court to give the land to him My question is, will the case stand on his 2 claims? Will thr be a adverse possession?