Books for 4yo girl and 2yo boy? Wonderful suggestions required.

[YunoWhatYouDidLastSummer]

Dd is 4 1/2
Ds is 2 1/2

I am making them an Amazon book wishlist for Christmas. Can you recommend anything wonderful?

I find 4yo dd easier to buy for than 2yo ds (possibly because he already has all his sisters books to love?)

I am particularly interested in longer books to read to dd (eg one chapter a night sort of books maybe?)

I would also love a REALLY GOOD recommendation for a dinosaur book (2yo ds) and a space / planets / solar system book (4yo dd). There are hundreds of both around, but I would like a GOOD one.

Plus, of course, anything wonderful that they absolutely must have :)

don't know about the 4 1/2 year old, but my nearly 2 1/2 year old loves:

The Gruffalo (and the Gruffalo's child) and most things by Julia Donaldson (Zog, the newest book is good)
Anything by Oliver Jeffries (e.g. Lost and Found or Catch a Star)
Fairytales (he has an Usborne book of fairytales which he really likes)
We're going on a bear hunt
Hairy McLairy books
Aliens love underpants
Penguin
Big Red Bath

HTH.

My DD1 is 4 and her favourite book is this. She can't read it alone but the information is so well-presented that she will look at the pictures for ages. There's a good section on space too.