My cousin is a wonderful person, she is a feminist, ecologist, etc.. activist, she cares a lot about people and I really love her (I see her and her family ~once a month for the weekend and I spend some holidays with her. I also spent two weeks at her home when I was looking for an apartment).
As a feminist, my cousin knows a lot about "mental load" and the problems with chores distribution in a couple's relationship. However, since I'm at her house very often, I couldn't help but notice that there is a chores distribution problem in her relationship (she seems to do much more than her share).
I know such subjects can be sensitive and I don't want to "make a mess" of her relationship with her husband. However, I believe that she might not be really aware of this fact right now and I think that, if she "knew", she could talk to her husband which would (at least partially) fix the issue and life would improve for her.
So, how can I tactfully talk about that with her, without coming off as someone who likes to "put oil in a fire"? I just want to help her see that there might be a problem here (but if she tells me there isn't one, then there isn't one).
Notes and clarifications
I don't know if this causes problems in her relationship. However, it might very well be the case and, even if it isn't, she will probably be happier if she had fewer chores and more free time.
I see no reasons why this would have been mutually agreed upon, since her and her husband basically do the same job.
Why don't I just mind my own business? Because I care about her and want her to be in the best relationship possible
I'm not planning on making any accusations, I just want to tell her something like "Hey, I have observed that you do a lot of chores, I was wondering if there is an issue there?"
I don't think my cousin should be unhappy, I'm wondering if she is. I know talking to someone about your problems can be helpful and I just want a conversation here.
The answers here made it clear to me that you have no idea what my relationship with my cousin is. I won't try to convince you that I'm legitime and close enough to her to talk to her about it (because I have better things to do). But I would appreciate less doubt in me and more help to tactfully bring my concerns to her.