1. You have not informed how and why you were married to the said disabled husband?
2. However, you should not lodge a police complaint u/s498A against your MIL and SIL for dowry harassment,
3. After that file a DV case cagainst them,
4. If your husband has any property, you, your son and your MIL are the joint owners of the same,
5. You can file a partition suit claiming the share of yours and yoyr son on the property of your husband,
6. You have nothing to do with the said Rs.30 Crores property unless your husband has any share in it.