I have a great neighbour. We talk almost daily at the fence, walk to the school together, and put each other's bins in and out.
She has 3 boys, and the youngest is 4 and is the same age as my DD. They attend nursery together which means we usually walk back together etc.
With the nice weather the kids have been playing outside a lot, sometimes they come over to my garden (often without asking) and very occasionally my DD goes to theirs to play on their trampoline.
The youngest however is very nasty I find. He often throws my DD toys in the air and they brake, call my daughter names and makes fun of her, and if on trampoline he will literally start really kicking and punching her. I say things like 'please stop that' or 'keep your feet/hands to yourself' the problem is my neighbour doesn't supervise them at all and doesn't see what happening, or does and just doesn't bother. I'm out there all the time as I have another young DD that I wouldn't leave alone.
My DD is covered in bruises from it, and now I have a broken bubble gun and toy kitchen.
How would I word it with her? We get on really well and I don't want to upset/embarrass her about her sons behaviour but I'm getting really upset about him hurting my DD.