The church says who has spiritual authority over who and how that authority flows downwards. A priest must get authority from a bishop in order to perform an exorcism. Other people have legitimate spiritual authority over their own things and over some people without being priests or deacons.
A priest can bless anybody (not sure if he can bless a bishop but let’s put that aside for now). The father of a family can bless anybody in his family; he can bless his wife or his children. Similarly, his wife, the mother of his children, cannot bless him because she does not have authority over him, but she can indeed bless her own children. The children cannot bless their father or their mother except under special circumstances (like, say, if the parent has slipped into mental incapacity) because, in the normal scheme of things, they are not normally granted that authority.
I myself, being unmarried, cannot bless a wife nor any children, although I can say binding prayers to
clear the air (send any spirits not of the Holy Spirit to the foot of the Cross for Christ’s judgement) of a house if I own one or an apartment if I am renting one.
Similarly, I think I can bless my cat because I think I have that authority . . . I think . . . hmm . . . not sure about that one . . .
So, yes, women can dispense grace if they have that authority.
PS: Can a Mother Superior bless the nuns she has authority over? Not sure about that one, but I would guess so. Can the nuns bless the Mother Superior? My guess is probably not, although again I am not sure about that one. If the Mother Superior became deathly ill and was no longer capable of carrying out her duties, and if a priest or bishop raised one of the nuns to the position of Mother Superior, I suspect that the new Mother Superior would have the authority to bless the old one. Again though, that is just a guess on my part.
Can a nun bless me? I don’t know. I rather doubt that I can bless a nun though, or indeed anybody else at all.
I came to these ideas from listening to exorcists like Father Ripperger speak about whether or not any given person has the authority to caste out demons in the course of an exorcism. I think other priests have spoken on the general issue of authority too. For me, this is mostly just priests talking on youtube, and I am assuming they are telling the truth. If somebody can point out any mistakes I am making, I would be eager to have the record set straight.
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