@bushwhacker2k I don't think it's that she's aged all that much in the story since the last times we saw her, so much as she hasn't been doing well recently and that was mentioned a little bit ago I think. The Glow looked a bit worse for the wear when Yulian called him on the magic mirror too. Maybe age is actually catching up with them both and all, but I can't seem to put a certain other wife, with a son who's third in line, constantly looking into assassination methods out of mind for some reason.
She was playing with the idea of poison back when Top Wife slapped her shit for getting mouthy in a meeting. Then had her nephew try to hire assassins by throwing money in a hole. That stuff has been on the back burner on low heat for a long time now, and some shadowy figures are talking about this being perhaps the last chance to get rid of Yulian. The game is afoot and some of these fools don't even know they're playing.