Recently had new neighbours move in below us (it's a large converted house consisting of a one-up and one-down flat) and they're absolutely lovely. Considerate with their music and tv levels given we have a baby and a toddler, always apologetic if I've had to take in a parcel for them - just generally really nice people.
However, a few weeks ago I noticed two new cats in their garden (the bottom flat has the back garden and we have a spiral staircase leading from our balcony outside our kitchen, in to their garden as a fire escape). Given we've lived here for two and a half years, we know which house has which cats, so I immediately made the link between these two cats and our new neighbours.
I wasn't bothered at all, we're cat people, love them, but it is in our tenancy agreement (and evidently downstairs too!) that no pets are allowed. A few days went past after I first spotted the cats, and the cats started sitting on our balcony by our back door. Again, not a massive issue, they wasn't causing any trouble and our balcony isn't used for anything other than keeping our food bin and recycling bags on.
But then, whenever I tried opening our back door, I had to start fighting away little cat noses and paws that were desperately trying to get in. When I'm cooking of an evening, they're up against our back door meowing!
Fast forward another week or so, and their cats are coming in to our flat! I like to have my kitchen window open to air out the flat as I can't have the lounge or nursery windows open due to small children, but the cats come in through the kitchen window and stroll about my flat. I like to have the kitchen door open in summer too, to get a nice breeze coming in, but now I can't see that I'm going to be able to do that when the weather picks up.
I spoke to neighbour the other day and made him aware what his cats were doing and he said he was going to put some things at the bottom of our fire escape (which can be easily moved by us in an emergency) to block his cats from getting up. He did so, but cats being cats, they just knock it over and stroll on up.
Today, I was making my bed and heard my toddler going 'cat! Cat!' From the baby gate across our lounge door, I turned around and sure enough, there was a cat in our hallway. I only had the kitchen window open maybe a palms width and the bugger still squeezed through!
If I see the cats just as they're about to come in, it's not a huge problem as I can just pick them up and put them back outside. But my issue is that I have to put my baby down for naps throughout the day so can't always see what's going on outside of the nursery, and I don't feel like I should have to have my windows shut to stop other people's pets coming in to my home. If I don't see the cats come in, they could easily make themselves comfy on our bed, our go in to our lounge where our boisterous toddler could potentially antagonise them and end up getting hurt.
I know cats will be cats and there's not a great deal our neighbours can do about it, but (as nice a person as I am, and a cat lover too) I'm reaching my limit and don't believe it's down to me to keep my windows shut to prevent neighbours pets coming in to my home.
What should I do?