I "think" I'm a bit unclear here.
My wife and my granddaughter have been living with us
So who is "US" if not your wife and grand daughter? I'm going to assume you meant to say;
My granddaughter has been living with my wife and I
Where is your daughter, who of course, is the child's mother? Is she working and producing taxable income in 2018? Maybe she lives with you too, and what you mean to ask is if you can claim your daughter and grand daughter on your joint return?
I really need some clarity here so I can at least "try" to help without wasting your time and adding to any confusion like I may or may not be experiencing now.
