Can kids suddenly "change" or am I wishfully thinking?

[PaperFlower]

I have two boys and they couldn't be more different. My eldest (11) is very sensible, hard working, mature, polite etc and my youngest is a blonde version of Dennis the Mennace. Always in trouble at school, scruffy, silly, immature and cheeky. He was that bad, he was almost suspended from school at one point.

Anyway people have always said to me "they change suddenly, you could end up with a role reversal in a few years".

Anyway I don't wish to speak too soon but for the past few months, DS2 seems to be changing. He is still quite stroppy but he's stopped name-calling and shouting. He isn't half as cheeky as he was. He completes his homework on time and takes it back on time (this is a major thing considering he went for an entire year with NO homework return at all) and this morning he asked me if I minded him running on ahead as he didn't want to risk being late for school!!! me and DS1 just looked at each other and DS1 said "what has got IN to him lately??" lol I watched him as he ran to the lollypop lady, waited, crossed sensibly and thanked her as he passed. Even she looked confused!

And this morning he was in an acheivement assembly. (first one all year). Tonight he is going to camp with cubs and I said to him "you won't be able to take your duvet like you'd hoped" and expected a massive row ... he just turnd and said "ok, mum". ???

Wishful thinking or could the "demon child" be changing? he's 9 and has ALWAYS been a handful so this new behaviour is quite shocking.

dd is just 3 so don't have direct experience, but just wanted to say that my brother was a right terror as a child. Very destructive, hyper-active and a consummate liar! At 11-12, he started to mellow down a bit, and slowly got more interested in academics and started actually obeying rules (though not with much grace). He's now 28, an actuary and sooo responsible I could even call him boring!

My two girl cousins 3 years apart in age did change personality a lot (oldest 10 years younger than me). I used to see them once a year for a two week family holiday and we'd spend a lot of time together and I was often amazed at the difference some years.

One year eldest would be chatty and youngest shy, next year it would have swopped and eldest really quiet. In general the youngest was the most outgoing and easy going as a child, but is now (in her twenties) much quieter and shyer than her sister who seemed more thoughtful as a child.