Is tejaswini from the og chavan family

I was curious to find out whether the mohit in season 3 is the same mohit from season 1 at the beginning, but I lost that thought after I saw him married to two woman, and none of them was karishma, but recent googling revealed that mohit from season 3 has parents named omkaar and sonali, and Wikipedia also revealed tejaswini's last name as chavan, if mohit was from the og family, then what happened to karishma, and when did omkaar and sonali have another son and dil, and why are they poor, and most importantly what the actually fuck happened to our gossiping queen sonali, why did she just turn into every other old grandma of the family.