Snakes in the crawlspace?

Sorry if I posted this in the wrong group. But How can I tell if there are snakes in the crawlspace?

That ^ was in the concrete blocks when I removed a vent, but it had a ton of cobwebs on it, idk I’d that means it’s extremely old, or not.

There’s a cat under there that had her kittens and I want to check and make sure the kittens are ok. Especially since it’s about to start warming up outside. I haven’t heard them in a few days.

There is the mother cat. I can see her from the vent. I can’t see the kittens though. 😰