The Lok Sabha secretariat has sought an explanation from Robert Vadra, son-in-law of Congress president Sonia Gandhi, for his Facebook comment allegedly criticising the functioning of parliament."A show-cause notice was served on Robert Vadra on July 25 for his Facebook comments. He has been asked to reply within seven days," an official told IANS on Monday."After getting a response from Vadra, the Speaker's office will decide whether the matter should be referred to the privilege committee or not," the official added.Reacting to the notice, the Congress said these issues needed to be answered by the individual against whom the notice was issued."I have no doubt that as and when it is received, it will be adequately replied to, keeping in mind the dignity of the house," Congress spokesperson Abhishek Manu Singhvi told media persons.In an apparent bid to counter the opposition demand for the resignations of BJP ministers, two party parliamentarians had moved a privilege motion against Vadra last Thursday.The motion was moved by BJP chief whip in the Lok Sabha Arjun Ram Meghwal and Prahlad Joshi, Lok Sabha member from Dharwad, Karnataka.Vadra, whose land deals in Haryana and Rajasthan are being probed, talked about "diversionary politics" and "so-called leaders" in his Facebook post on July 21, the first day of the monsoon session of parliament."Parliament begins and so does their petty diversionary political tactics. People of India are not fooled. Regret to see India led by such so called leaders," Vadra also tweeted. IANS