Your question brings back all of my boundary crossings with my Ts, past and present. Usually when I saw my former T in the community, it triggered me more than satisfying my curiousity. I attended a class that I knew she also attended, and I had a perfect right to be there, and went with my own friends. But it was never good. I watched her every move, and she knew it too. It made us both uncomfortable. There was too much transference going on for me. I wanted her to be my T when I saw her elsewhere, but she wasn't. It was very difficult though it got easier because I couldn't avoid her when our paths crossed.

Even if the other reasons to go are valid, you're going to have a lot of feelings if you go, and I don't think they will be about her father's art. It's too sticky and potentially triggering the way I see it, and though you are curious, I don't think it's a good idea even if your T gives you permission to attend.

Didn't you have problems with boundaries with your former T, that ended badly? Is this a pattern? I totally understand if it is. I think discussing with your T why you want to go, after the fact, would be more productive.