My mother-in-law is my joint sponsor, because my wife currently is not working. I need to know how to calculate household size because my mother-in-law lives with my sister-in-law. My sister-in-law does not economically depend upon her, because she's receiving disability benefits. She is 46 and unmarried. Do I still include her in household side for I-864 affidavit of support? My wife also has to fill out an I-864. Do I still need to be in her household size as well, even though she is not my joint sponsor?