Irini has spent her life never feeling wanted, not from her parents who sent her to live with her aunt and uncle, and definitely not her aunt and uncle. Growing up in such a manner has left Irini a very insecure person who often makes bad choices, despite being an anesthetist. Why did her parents keep her sister Elle and not her, especially considering everything she knows if Elle leads her to believe Elle is crazy? That's the ultimate mystery Irini is tasked to find out. If You Knew My Sister is riddled with action, plot-twists, and doubt. Elle makes for the perfect villain, always there even when she isn't. Watching events unfold for Irini had its suspenseful moments, however, I feel like the ending was rushed. A good portion of the plot twists occurred in the last few chapters. I feel that if an author is going to spend so much time building up a good storyline that leaves you constantly guessing for the truth, then the ultimate truth shouldn't be rushed. But overall it was a good, suspenseful read.