The Secrets We Keep by Mia Monroe

Only a jerk would steal his sister’s man.
I told myself it was a harmless crush on my very straight, future brother-in-law, until one night we crossed a line.
Everything shifted as forbidden passion simmered between us, but we vowed to keep it buried and our family intact. I saw the cracks between them, but for some reason, breaking up wasn’t an option. I didn’t know then how many things we all hid.
When it all collided, the decision we made changed everything.
And if the truth comes out, the secrets we keep could destroy our lives.