Daughter in Law and her parents have indifferent behaviour towards us

Dear Sir / Madam, My name is ram Mohan and we live in Ghaziabad. I have two sons. Elder soon and his family that including our grandchild stays with us. He is self-sufficient and takes care of his family financially. I have one younger son also and he is married. His wife and in laws are Punjabis where we are bramhin. His marriage was a love marriage. Initially, we were against this marriage as the girl was 4 years elder to him but somehow bowed to his desire and got them married. Since their marriage, his wife and the in laws are very jealous of our elder son and his family. They feel: 1. our elder son stays with us and does not pay any rent. Whereas the younger one has to pay 25000 rs a month rent. 2. Our grandson is getting all our attention and the family is at ease without any worry. 3. How would the child of the younger son be brought up as younger son and his wife, both work? 4. There is always a demand for 4a. Settle the younger son for his house. We paid 10 Lac rs for