I loved the first book so much that I just had to buy the sequel as soon as it came out! This is a bit more Christmassy than the first one (featuring Father Christmas) so it's probably best done as a late Autumn topic and considered in parallel with, not isolation from, the first book. It could be read alone, but the themes of 'be true to yourself' continue through this one and the characters are developed, including revisiting the Truth Pixie's home and discovering her true name, meaning that they work best as a pair of books. The original themes are built upon with the addition of a bullying plot (Aada is targeted primarily because she's friends with the Truth Pixie at school), Aada encountering new difficulties with her life, and a separation of Aada and the Truth Pixie. In the end, the core message prevails that you should, foremost, be you - and ignore the bullies.
As with the previous book, it all rhymes and is essentially an incredibly long poem (possibly inspiring similarly-styled work from the children). The single exception is Aada's letter to Father Christmas - it would be interesting to see if the children can immediately identify that that section doesn't rhyme. It has an imitable art style, and although the plot is a little more sophisticated with bigger twists, it can be fairly easily transformed into a story board and re-constructed. It's suitable for Year 2 and up, with its only major downfall being that it's a little too long to suit Y1 and EYFS - it would take multiple sessions to reach the end.
A few of my favourite quotes:
"But the fears you feel won't be less real, by trying to make people feel what you feel"
"But why be normal, when you could also be you?"
"Don't try and be something you really are not. Your one true self is the best thing you've got."