My husband left our eight kids and me for a woman young enough to be his daughter. A month later, my phone rang at 2 a.m. “You have to stop my mom,” he begged.

When I learned what she planned to do to him, I thought karma had finally caught up to him — but then I realized I’d made a huge mistake. Looking back now, the signs were there for a long time. My husband’s best friend, Mark, frequently visited us.

He usually brought his daughter, Lily, with him. Lily practically grew up in our house. She was the flower girl at our wedding.

She was eight when our first child was born, and by the time our fourth child came along, she was old enough to babysit occasionally. Our kids adored her. As our family grew, Lily was like an older sister to them.

And somewhere along the way, Daniel started paying a little too much attention to her. She’d come over with Mark, and the three of them would sit together on the back porch while the younger kids played in the yard. Lily would sometimes join the games in that indulgent way that a 20-year-old might, but Daniel would eventually call her back to sit with them again.When she babysat, Mark often called her into his office to chat after we came home. At the time, I told myself it was harmless. She was just part of the furniture in our loud, chaotic home.

Maybe that was part of the problem. With eight kids running around, there was always some crisis to solve. Someone was always losing a favorite shirt, a toy, or a pair of shoes.

Sibling arguments formed the soundtrack of our day-to-day lives. Daniel used to stand in the kitchen, shaking his head. I’d laugh.

I thought it was a joke. Then there was Daniel’s mother, Margaret. She wasn’t cruel; she didn’t need to be.

One look from Margaret was enough to make you feel like something unpleasant she’d scraped off the bottom of her shoe. I got that look often. Once, shortly after Daniel and I got engaged, she pulled me aside at a family dinner and said, “You seem like a very nice young woman, Claire, but my son has always had significant opportunities ahead of him.”

Her meaning was clear: I wasn’t good enough for her son.

I understood it, in a way. Margaret had built a hugely successful business alongside her late husband, and Daniel stood to inherit all of it. She had reason to be protective, but that didn’t make “the look” sting any less.