Is Yellowish, Bloody Discharge From Breasts At The Age Of 47 A Cause For Concern?

Ok, I do not know how to ask this but my mother is 47 years old. & Her breast there was milk coming out of them for awhile now, but now its yellow-ish then it looks like there is blood in the discharge. Do you think it s something serious to worry about? Like what to you think it might be. & What might be causing this to happen because she s not pregnant. So we are concerned?