What followed was an open letter to the Delhi Chief Minister from the lawmaker's mother, Annapoorna Mishra, a former BJP politician.
"How many lies, Arvind? How many?... Lies will not help you. Be afraid of god," Mrs Mishra says, sounding bitter and angry in her letter in Hindi to "Arvind".
"I never thought my son would ask you questions and you would avoid them," she writes, adding that "whenever I met you, you always talked about probity in public life".
"Remember you came to my house and said to me - 'I want to take Kapil in the party and make him contest the election but he is not listening'. He only wanted to be part of a movement, but you came to me saying you need him," she says.
"Today, your people are calling me corrupt too. And you are silent."
Mrs Mishra sought to remind the AAP chief that in 2007, when there was "neither a movement nor a party", he came to her "Mohalla Sabha" or neighbourhood meeting.
Saying that she was proud of her son and his protest, she said, "You worked with Kapil but never understood him. He is very stubborn. He hasn't eaten anything for three days. As a mother, I request you to give him what he has asked... just information. He is not an agent of anybody but of the truth."
Mr Mishra has since Wednesday been on an indefinite hunger strike in a tent at his Civil Lines residence, demanding that details of foreign trips made by five top AAP leaders be made public. He was sacked last week, hours before he went public with a massive corruption allegation against Mr Kejriwal. He alleged that he had witnessed Mr Kejriwal taking two crore in bribe money from another minister, Satyendar Jain, and that Mr Jain helped the Chief Minister's brother-in-law Surendra Kumar Bansal with a 50-crore deal.