Neighbours nuisance

My downstair neighbours keep complaining to us about us walking in the house which disturbs them & them falling sick due to it.On 1 occasion they even bought cops to our house l8 at night when me & my girlfriends were having a sleepover even the cops agreed we werent making noise bout they being senior citizens they had an upper hand. Now we cant fly in the house right.We being a young married couple we stopped having friends over after the cop incident but these neighbours still keep complaining to us about us walking heavily.What & how can we deal with this.they are gujjus living in a catholic locality & they have a problem with everything & everyone around.like car reverse horn too is a problem to them.we are just fed up.would like to know of a solution for the same.