He was intent on making sure she didnt sign anything. And he's determined to keep her in the house
Obviously Moniya is the second daughter of the Singhs. I think that maybe Baba was married to the daughter of the house and he took Moniya to raise her himself, away from their influence
I think once the family finds out that Moniya exists (or is still alive) they will want her to live with them at the Rajmahal
Yuks