Pihu and Juhi maa

When Priya went into the coma, Pihu was around 16. She was basically grown up, an adult almost. Why does she call Juhi her maa? I just dont understand the relationship. At 16 , i would never have been capable of calling someone else my mother much less try to get her married to my dad. I feel Juhi enables Pihus bad behavior and makes reasons for it whereas Priya is trying to teach Pihu the difference between right and wrong and morals.