Can anyone tell me if the family income is taken into account at all if an elderly parent lives with them and has pension credit?

I have a query for a man, aged over 65, who owned his own home and got PC(GC). He has sold up and moved in with his family for care needs. He has told DWP, and they have asked him for his daughter's and partner's weekly income on the change of circumstances form. Is this just a standrad question, or will it be taken into account at all?
He is worried that telling them might mean he loses his PC.

I cannot find anything that mentions this in guidance. By the way, we have advised him that the capital from the sale of his home will affect his PC, unless he has an assessed income period!

No the family's income should not be taken into account. Was your client getting the Severe Disability Premium previously as part of his Pension Credit? They may just be checking if he is still entitled to it based on his family's circumstances i.e if any of them are getting middle rate care component of DLA (in which case he would still be eligible for the SDP).