Bedtime read-aloud with my son

I read aloud to my son every night before bed, and I'm looking for our next book. I've done my fair share of sharing my favourites from childhood, but at the moment, it would be nice if it were something new to me too.

My son is 5, but we usually do something a bit above his level for the bedtime book, as I think bedtime reading is good for stretching his vocabulary and ability to follow more complex storytelling and themes, etc. Because it's read aloud, I don't mind "editing" things that I don't think he's ready for (i.e. language, sex, violence), but obviously it's helpful if those things are relatively mild in the book to begin with.

We are just finishing The House in the Cerulean Sea. We've previously read The Wild Robot series, which he really enjoyed (and we've passed on to many of his friends as well, so it's been nice for them to share that story). We read The One and Only Ivan (the whole series), and he liked that as well, though I was less into it (it was ok). I also read him Project Hail Mary (Andy Weir), which he enjoyed, but was maybe slightly too difficult – obviously the science was beyond him, but the main bit that I think was tricky was the jumping backwards and forwards in time.

We've covered lots of classic children's books (The Secret Garden, Narnia Series, The Railway Children, Matilda, The Borrowers), but right now, I think we're in the mood for something newer.

Any ideas?

ETA – something summery would be good – something that embodies long summer days, summer camp, outdoor adventures, etc.