A Sister's Promise by Pam Weaver

Can a secret sister help her find her way?
Worthing, 1931
Raised in the grandeur of Muntham Court, young Millicent has always felt like the black sheep of her family. Between a vindictive mother and a conceited older sister, her only ally is her doting father, Charles.
Brought up in the traveller community and always on the move, Lena’s life has never been settled, but it has always been happy thanks to the support of her loving mother.
When it is revealed that Lena is Charles’s illegitimate daughter, Milly finally has a chance at true sisterhood. Thrust into a world of fairgrounds and new friends, her excitement is short-lived when she realises her mother must never know.
Six year later, when both girls lose their father suddenly, they need each other more than ever as they forge their own path in the world. But Milly is harbouring a secret from Lena that risks losing her forever…
Can they help each other face their futures, or will old lies tear them apart?
A gripping and emotional drama from the Sunday Times bestselling author, perfect for fans of Dilly Court and Katie Flynn.