I’ve just had a knock on the door from our semi detached next door (their house is attached to our house). They have 2 girls, 8 and 6 and they’re lovely, but very precocious and whenever I’m in the garden, they pop their heads up over the fence to chat.
They also ride their bikes up and down our drive (both us and next door have long drives with a fence between them but a gap at the end nearest the houses and the kids ride up and down both drives like a racetrack because it forms a loop with the fence in the middle). The other day I was coming home in the car, and the kids came tearing round the corner on the drive and I nearly hit them. They then didn’t move and completed their lap before getting out of the way which has happened a few times now.
I spoke to their mum after the incident and just said ‘I’m happy for the kids to ride their bikes on my drive because it’s a great racetrack and better than them being on the road, but please would you remind them that when they see my car, they need to go into your drive as fast as they can and stay still until I’m parked so they’re safe?’
She said ‘I can but also be more careful when you’re reversing in, you really scared them’
Now, this put my back up because she’s never actually asked to use my drive but I but my tongue...
Anyway, last night I was in the garden briefly and the kids popped their heads over the fence and in the course of the conversation the girls said ‘mummy says we need to be careful when we’re on the bikes’ and I was really pleased so said ‘yes that’s right, when you see my car make sure you’re on your drive so I can see you’re safe’.
I thought no more about this until 8:30 this morning when I got a knock on my door and it was their mum - she was clearly fuming and said ‘I don’t need you giving my kids safety warnings, keep your nose out of my parenting’ 
I said there’s clearly been a miscommunication somewhere but that I often chat to the girls over the fence and had just confirmed to them that I agreed with her warning she’d clearly given them she said ‘well don’t they’re just children and I’ll report you’. I asked what she’d report me for and to whom and at that point she stormed off.
I came back inside and while we’d been talking, the girls have thrown an old hosepipe and some branches off their cut down tree over my fence which they’ve never done before 
.
I want to go next door and say the kids have thrown rubbish over the fence and can she come and retrieve it but I really don’t want to start a neighbour war…
WTF do I do?