Some kind of creature...?

Just for context, I wasn't here to experience this, the story was told to me by my stepbrother, my dad, my grandma, and my stepmother. All of the details may not be correct but this is what I personally remember, this was told to me during December of last year! I don't believe my English is very good as well so the description may be confusing, sorry about that.

I think last year around 2022, all of the people listed above went to this cottage in the woods that they owned/rented. I think they went there to pay respects to my grandpa who died in 2017.

One night, they were all sitting around in the cottage and they suddenly heard TWO bangs on the roof, I believe the cottage shook. Everyone went outside and nobody saw anything. When this was told to me, they described that it felt like a giant human ran across the cottage on the roof. It didn't sound like an animal because it sounded like two legs running across the roof, not four. And even so, it must've been big. I'm pretty sure the people who lived around that area where the cottage was heavily believed in Bigfoot.

I think I remember asking if the experience could've been our grandpa who died in 2017, my grandma jokingly said something like "he wouldn't want to scare us like that". I don't believe they were lying, because 3 adults and a 17-year-old were willingly trying to get me to believe them. I'm not sure what this could've been, is there some kind of logical explanation to this or was it paranormal??