Need advice. We live in an end terrace and yesterday I noticed that someone had been chalking on our wall "Shit" and "f**ker" and "dasted" and "nob". They've also done it on the wall down the road.I asked our next door's daughter who plays out a lot (on her own - she's just turned 4 
She said it was her brother and his friend (aged about 6) . I spoke to his Mum who spoke to him. He said it was such and such a person, an older boy who lives where they used to live.So either him or his sister is lying. I am not sure if it was him or not, but it seems awfully convenient to pass the blame on to someone who lives elsewhere.
I have reported it as an incident and have an incident number, but I am not sure about asking the police to attend. The operator said they will and sometimes the presence of a policeman is enough for some kids. At least it has washed off, but I am annoyed because my kids are small (aged 1,3,5,8) and I don't want them knowing these sorts of words.Also, Mum doesn't seem too bothered about it, though I did hear Dad phoning someone asking who did it.
WWYD. Should I draw a line under it now as long as it doesn't happen again, or should I call out the police?
I envisage having to call out the police at some point for this family as since they moved in they have had a few loud parties that have gone on until 2am. I already spoke to their landlord.Should I save the police call until something more serious happens?