Yes. Having family help out on a 1-man show is an entirely different beast than hiring a full-time employee with wages, taxes, and healthcare. One of these two is a life-long trusted human that you've shared numerous life experiences with, the other is not.

Looks like the brother just does the merges? (which are mostly automatic) so IMO best it matters because it's still mostly a one man, or at least a one family operation - i.e not very resilient to random acts of nature (which backups are supposed to protect from)

Having them be two brothers makes for a lower business continuity risk than having it be a business owner + 1 random employee.