You can buy Billie's shirt here from the Lavish Alice website. Unfortunately Billie's trousers aren't available online but you can view them here on the US based Zara website. Be sure to check your local Zara store if you'd like them as they might still be available in-store.
I have already blogged about the playsuit Lucy Mecklenburgh is wearing in the photos linked above and you can view that post here.
Item image via Lavish Alice.
