Designs on a Duke (The Bluestocking Scandals Book 1) by Ellie St. Clair

Her secret will save a legacy…
The daughter of a famed architect, Rebecca Lambert has been raised among the nobility yet understands the circumstances of her birth. As a common woman, she will never be able to pursue her passion and become an architect as well — at least, not under her own name. When her father slowly begins to lose his sensibilities and falls into debt, Rebecca becomes far more than a secretary, but rather the designer. No one, however, can ever learn the truth.