Property dispute and maintenance case under senior citizen act 2007

Hi sir/mam I purchased a house in 2005 and I’m living with my family.but in 2009 my father’s brother my uncle start living with use in delhi before he was a government employee as he don’t have children me and my wife allow them to stay with use. But in 2019 his wife got paralysis and before this we were only taking care for them food clothes,etc. But now as i’m 53 old and my wife is also not well we are not able to care of them as we are also not well. So now he is claiming that I’m his adopted son and he file case of maintenance under senior citizen 2007act and also claiming that i have 2 house which is in my name and my wife’s name he buy both house. As now his greediness become more he want my property as well as asking for 20k per month for himself and for his wife. He is ex government employee and he has pension 28k plus as well as all medical expenses are free from government.He slapped me 3 time and pretend like he the one who is get hurt by us. Please help me.