I have two cats. Neighbour has two cats. Mine very rarely venture out of the back garden and they certainly don't go into anyone else's house.
My next door neighbour is only young with two small children. She has two -extremely adorable cats - but they always seem to be outside and I can't open my back door without them darting in to find my cats' food bowls. I've seen them eat and they're ravenous. although they appear healthy. They seem to prefer sitting and sleeping in my garden than their own. They're literally always there.
I like having my French door open but it's getting to the stage where it's a major operation: make sure kitchen door is closed, make sure living room door is closed, alternate the two. My DD and I actually use water pistols on them to deter them, which works, but we can't stand guard with them all day and evening.
My cats swing between getting agitated and ignoring them.
I don't know why I'm posting to be honest. I thought about a cat screen but I believe they're not that effective. Thought about one of those electronic cat deterrents but that's going to affect our cats. Thought about going to speak to the neighbour but she's otherwise a good neighbour and I don't want any issues.
sigh