Women Share on Undivided property

Hello, I’m Venkat from Hyderabad, don’t know anything about the legal matters, I just selected the category as property law as my question is something is related to property. I need advice in below situation, to proceed further. Case: My mother-in-law and her elder sister (let’s say X and Y for now) are two children’s of their parents. Both X and Y got married and had the grand children as well, X and Y‘s parents passed away without making any will, there is some undivided property, documents related to that undivided property is with Y. here X is expecting the majority of share on the property which is not at all ok with Y, several talks got failed with mediation of the common relatives. Recently X husband sent a lawyer notice, calming that Y has taken the loan on common property without out his knowledge. My questions: 1) Could X husband supposed to send lawyer notice? If not could we apply for loss of reputation on this? 2) What I have to do next, with respect to the layers notice? 3) Would law support Y to keep half of the property? Please need you advice. Thanks in advance Venkat