I guess it depends on where you are from and how things are said. However unofficial the brother/sister relationship between Delta and Omega, it is very real in many places and is taken very seriously, nut that is up to individual chapters.
On the question at hand, it depends. To me, a Delta can say "my Bruh/s". But in some places, Omegas are simply known as or referred to as "da Bruhs" by other sororities because in their neck of the woods, the term only referred to men of Omega (especially on the east coast like in Philly and NYC). I know that AKAs have asked me before "where is the Bruhs cookout?" or "are the Bruhs stepping in the show?", with the term being used in the generic sense and not the possessive sense as a Sista of DST has the familiarity to do so.
That probably didn't explain anything, but thats my take on it. I guess it really depends on where you are from and what you are used to.
BTW, thanks CrimsonRage for feeling so possessive. Its nice to be wanted by someone other than the law
