Northern Residents Deduction- multi generation household

I have a client who lives in Fort McMurray and has never claimed the Northern Residence deduction.

Question: is she entitled to the basic deduction, as a grandmother living with her grown children who claim their own basic plus additional deductions for the household? I think she would be, but am getting confused as to whether she does or not. She is not dependent upon her grown children for support. She does not live in her own self-contained accommodation.

See the section “Can you claim the residency deduction?” - if she is the only person in the household claiming a Northern Residence deduction, she can claim the additional residency deduction.