Books that say "it's OK to be caring/wear pink and still be a boy" and "it's OK to like diggers and still be a girl"

[drspouse]

I have Phoebe and Digger but all the books for boys seem to say "if you wear a dress you are a boy".

TBF my boy doesn't really want to wear a dress all the time (a tutu for dancing is OK) and it's probably more about it being OK to wear pink (which he does like, he doesn't think it means he's a girl, but he STILL says "it's for girls").
But he is dangerously close to "boys are stronger than girls and boys fight/hit".

DD loves Katie Morag - she also likes Dogger and I'll have to try DS on them again.

I think they'd probably like Poppa Bombola as they are both into books for slightly younger children (they are 3 and 5).

Hmm I am slightly worried about the wall of pink... maybe navy with a pink collar? Or socks with pink toes/heels?