On Vampires and Cavemen

So I was laying in bed last night staring at the ceiling. My girlfriend was trying to touch my weiner but instead of thinking about boobies, my mind kept wandering to cavemen and how they dealt with vampires. I mean Im just going to take for granted that vampires are immortal so they were around when cavemen were. But what blew my mind was this. Where the fuck did cavemen vampires sleep!? Coffins weren't invented yet. You can see why this would be a big deal. without a coffin they would die in the sunlight. well unless they slept in a deep dark cave, but I would think all the caves were occupied by real cave mean or sabre tooth tigers. Im not sure a vampire would win in a fight with a sabre tooth tier, I mean Id imagine a werewolf and a sabre tooth tiger are about the same strength and size and werewolves can easily kill vampires as proven in the movie Underworld. So I guess my question is. Where the fuck did caveman vampires sleep?!