It is the premise of every other low budget horror movie ever made: a family moves into an old house and finds something that they didn't bargain for. It's not something that most people expect to happen in real life, especially not on the scale of an entire underground tunnel.
Nonetheless, this is exactly the case for Steven, as is revealed by his cousin Maya on her TikTok account @moodycakes. In a three part video, she takes a tour below the house with him and he reveals that underneath the building is a secret cave with a history that predates the home itself. First, he reveals the entrance, and the pair make it halfway down the stairs before Maya falls in the dark. After that, they make it down the staircase (complete with foreboding "enter cave at your own risk" sign) to reveal the construction below, as Steven explains what he knows of its history — including it being used to transport and store casks of beer and even as an underground bar during Prohibition.
There's no denying that the whole thing is more than a little strange, but it's also fascinating to think about living side by side with such amazing history. It's definitely not the kind of place you would want to explore alone, though, because that is complete 'first person to die' behavior.