Sita has made a nice painting to gife them. She & Urmila have decided not to show smiling face, so they can leave happily.
Mandavi & Shrutkirti decided to hide as a last resort. But the Dear disclosed their hiding place.
Wise Sita told them, they'll appeal for the last time, if they still dont accept, then their parent's wish will be obeyed.
Janak understood the situation. He respected the sister's wish.