Just an update - as I'd decided to keep it off this public forum, but now I'm annoyed enough to post. I talked to the other neighbour on the other side of their house, and she was as distressed as I was (her baby is even younger). Last Thursday, the kids were playing a football match and still going strong at 11 pm. So we texted and asked them to take it inside. I received a series of very rude texts from the husband, so the other neighbour and I went over together and were told the kids had only been out for only 10 minutes (it had been at least half an hour, and they were screaming and kicking the ball against all the fences) and that their kids were out of school (my kids are definitely not) and she closed the door in our faces. My other neighbour did get the mother to agree after that exchange that after 8 pm, the noise should be kept to a minimum - yet only three nights later, it's now 8:20 and the kids are screaming, yelling, and thudding against the fence. So I'm afraid we'll have to start complaining to the council. Unless anyone else has a better suggestion?