A buyer registered a land sale deed and mutation in 2011, paying property tax for nine years and receiving possession. Now, the seller's son is challenging the sale, claiming it's ancestral property, despite the nine-year delay. While the son can initiate a civil suit, his claim may be barred by the law of estoppel and limitation, especially if the property was self-acquired. It's advisable to consult a local lawyer to prepare a defence if a legal challenge is filed.