Walking Pathway for the owner behind my plot

HI, I have a plot in Kerala. We inherited the plot. There is plot just behind our plot and they are asking a pathway to walk from our land to their land. Our grandfather had brought the plot from their family in 1967 and it is written in our agreement that we need to GIVE THE OWNER THE FREEDOM TO WALK FROM FROM THE SOUTHERN END OF OUR PLOT TO HIS PLOT.It does not specify any permanent road to be given The Points to be considered here are 1) They have NEVER walked from our plot to their plot in more than 50 years. Their Plot has no other road 2) We have still considered allowing them to walk through our plot but they insist on having 3 feet of road. My queries are 1) Is their any rule which specifies the width of the road to be given in such case? 2) If I intend to file a case can I file it for just the 3 feet of plot (On the southern Side) which is disputed? 3) Will a case stop me from selling or doing any other activity in the rest of the part of my land? Kindly Advice