I need ideas to entertain the children over summer... help!

It's a love hate kind of relationship between my two, one minute they're the best of friends of friends and the next minute they're trying to get the other one in trouble for literally anything!

I struggle to understand their relationship so much especially when I see beautiful posts by other bloggers on how their children get on so well, maybe it's because there's a 4.5 year age gap between my two and the fact they have no choice but to share a bedroom means they don't really get their own space which can be hard for them both especially Oliver as often Isabelle doesn't want to go to sleep or she will mess up all of his lego.

I am looking forward to summer holidays and spending lots of time with my babies before September BUT I need to come up with lots of ideas to keep these two completely different individuals happy so please share your ideas! @mummymemories