After my mother passed away, getting my father 75/M married to my widowed mother-in-law 69/F, please suggest how to make this happen

Around 3 years back my mother passed away and I was very close to my mother, my father since then feels lonely and he is 75+ years but physically fit, he sometimes sits in his room and keeps staring at my mother’s photo and starts crying after sometime..while that shows how much he misses my mother but its equally concerning as it might have deteriorating effect on his health as well as he has a prolonged history of BP and Diabetes, so somehow I want to give him a comfort or someone whom he can talk to, be around him all time and be a good friend and partner to him so that he doesn’t feel lonely.. Now we being kids to him, I feel he doesn’t openly talk to us due to the age gap i guess, so I was thinking that he gets a companion of his own age. Now on other side my mother in law is a widow (younger than my dad by a couple of years), her husband and my father-in-law passed away long back before even me and my wife got married, she lives with her son / my brother-in-law who doesn’t do any work, he just wants easy money in life, so he gambles in stock market and there have been instances where he has lost lot of money in share market, he doesn’t take care about his mother, he got married 2 years back to a girl who does job but she shares her earnings with her mother and doesn’t bear my brother-in-law expenses, so my brother-in-law keeps borrowing money from my mother-in-law for his expenses..my father-in-law was in a government job so my mother-in-law gets pension and instead of earning money and giving to his mother, my brother-in-law expects his mother to bear his expenses..now seeing all this my wife is always worried about her mother but she is hesitant to ask her mother to come and stay with us because of the society, basically her concern is that if she has elder brother then that brother is suppose to take care of her mother and as a daughter its not her responsibility as per the view of the society, so this made me think that what if my mother-in-law gets married to my father, in that way it would be a win win situation as my father will get a companion and my mother-in-law can stay with us with all rights as my own mother with no guilt and no one in the society can also point fingers at her because she would be legally my father’s wife and my mother so she can stay with us with no issues whatsoever plus my wife will also be very happy with this since she no longer has to worry about her mother’s health or needs as I would become legally her son and I would take good care of her in the same way as I was taking care of my mother. I was very hesitant with this thinking earlier but I thought about it for a long time and i feel this would be a right thing to do and really want this to happen as I feel in the form of my mother-in-law even i would get my mother back, so I wholeheartedly want her to come and stay with us not just trying to pity on her. but I have a dilemma now that how should i approach my wife and my father and convince them for accepting this idea and moving ahead with it.. I feel that this discussion is going to be very awkward.. so i really need some good guidance and suggestions to make this happen..to start with I was thinking to invite my mother-in-law to stay over at my place for couple of days on some festive occasion first, so that both my father and mother-in-law get some time to interact with each other and then slowly we take things forward but to be honest I don’t think this will honestly work as this might take very long time for a bonding to happen between them.. I just want to make it happen as quickly as possible so please help with some ideas and suggestions