According to the USCIS site, the intending immigrant's income can be counted towards the petitioner's affidavit of support as long as the intending immigrant continues to obtain said income from the same place after obtaining a green card and must live in the same residence as the petitioner. Evidence establishing these two requirements would therefore be needed.
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DACA Approved: 10/09/2012; DACA Renewal Approved: 09/08/2014
AOS (245i) F2B: 11/10/2015; Biometrics: 12/09/2015; EAD: 02/16/2016; Interview: 09/20/2016
AOS Approved: 09/20/2016; Welcome Letter: 09/28/2016; Green Card: 09/30/2016