returns for an expired person

Mehul Sheth (Audit Executive) (73 Points)

12 August 2019  
Hi
my paternal grandfather got expired on 9.8.18.(last year)
Do I have to file the return for f. y. 18-19?
Also how do I verify the return if I have to file the same.
He did not have his mobile number connected to account number neither his aadhar connected to any mobile number.