Recently, a Madurai-based couple had claimed that the South superstar, Dhanush, is their 'biological' son. Now, the actor and his father, Kasthoori Raja, have sent a legal notice to this couple, asking them to stop making 'specious' claims regarding Dhanush. 'My clients call upon you both to desist from making false, untenable and defamatory allegations against them. Otherwise, clients will be constrained to approach the competent Courts to protect their rights. You both will also be prosecuted for causing defamation and consequent loss of their reputation,' the notice read. For more news and updates, stay tuned to ETimes.