What's the relation between dr.riddhima and dr.anjali,riddhima calls mom to sister padma and anjali calls her

aunty padma does dr.shahshank had 2 wife >>>?? then why shes not living with dem and why shashank not behaves with her like a wife????? i dont know bcs i started watching this after its 15-20 days..... pls tell me what's this all i will be thankfull to you!!!!!!!! DILL mill GAYE (star one).