How to make a one feel loved?

Hi,

This is happening in my would be's family. My wouldbe's mom died when he was in X grade. He has two younger sisters. His mom's siblings are living very close to their house and their families love these children very much. During his mom's last days before her death when she was sick, his mom's relatives misunderstood his dad being inconsiderate to his mom. This created a lot of misunderstanding between husband and wife. Mom's family thought that his Dad being a doctor should be more attentive to his mom. But his dad knows that the disease is too bad and nothing could be done. During this misunderstanding period, my would be's mom took one of their family friend in confidence and spoke the issues between husband and wife. The friend told all these to my would be's dad that created more problems between them. Later my would be's mom understood that talking to friend is not a good idea. She told her children to take care of their dad and made them understood that dad believes his friends a lot who may not be good. Also, their dad already got a bad opinion about his wife's family. Friends worsened their misunderstanding.

I should also mention that my would be's parents were a very loving couple till she fell sick. His Dad is a very emotional and very loving person. After my would be's mom died, her family understood that my would be's dad is a good person. But his Dad was so hurt and he did not want to renew the relationship. Whereas the children still loved their mom's family and their Dad. This irritated their Dad and he wanted to separate the children from the mom's family. So he left them at his siblings house in a nearby town. Children were not happy there and they cried a lot for a month. Later they came on their own back to their home and that too to the Uncle's house( mom's brother). Their Dad thought that the children are much closer to the mom's family and his loneliness and friends' bad influenced worsened everything. He started telling everyone how bad his wife (my would be's mom) relatives are and how much he loves their children and the children are ignoring him and hating him because of mom's relatives.
But the children though they love their Dad, still have good contacts with their mom's family. Their dad did everything for the children but still continued to talk to everyone bad about the children hating him and the mom's family.
He started doing the same thing to my parents. Now my parents too got soft corner for him and they think bad about the children and the mom's family.

My would be's dad is still under influence of his friends. One particular friend comes up with stuffs like if your son gets married he will ignore you further etc. My would be's first sister got married and she is living in a city (7 hours travel away). The wierd thing is even if the children goes to him with love and talks to him nice he tells "what so new today. you love only your uncle. why do you put up this drama?". Children get hurt, they try telling him that they love him but still nothing works. Talking to him does not help. Their first daughter did not even look for a job before marriage coz she have to go to a different city to look for job. she stayed back home for more than a year to take care of her Dad. still her dad did not understand their love. Their second daughter who is so affectionate to her Dad got upset because he once mentioned in front of all his friends and relatives that he does not know why they even call them DAD when they hate them and ignore them. She stopped calling him Dad.

My would be got him a car and wants him to take rest and he offered to send money for which his dad tells everyone that his son is telling he is too old and not fit for anything.

Earlier children were not so old. But now they are having families, job, colleagues and this action of their dad makes everyone think bad of the children. Even my parents have a slight thinking of the same. Ia m convincing them that my would be is not like that.

I cannot leave my father in law (to be). At the same time I cannot let him damage our reputation. What could be done? how to make him understand and throw away this deep rooted thought in him? My would be is abroad. His second sister is also in a college too far away. We understand he is lonely and that is the reason for his actions. Do you suggest a doctor? IF so whom should we go to? We cannot take him to a doctor because he will get very upset. We need a doctor who could advise us.

Thank you for reading my post with patience. Any pointers would help.