Using terms in separate parent-child select dropdowns

Nice plugin wherein I’ve loaded all my parent terms with children attached to them as per the instructions. Now for the hard part- I want to use these on the front end in 2 separate hierarchical select dropdowns so users can choose their parent state in the first, and then their child city in the second. In MS ACCESS they’re called “cascading dropdowns” and I’m very surprised at the difficulty in emulating this functionality in WordPress. I was expecting there would be a plugin that can do it but no luck thus far…Any guidance much appreciated…Thanks!