My husband used to leave every Saturday at 7 a.m. to coach his deceased friend's 8-year-old son, but when the boy slipped me a note, I collapsed.

"Mark?"

He jumped slightly. "I was just saying goodbye to her."

We turned around to leave and almost hit Leo, who was still there.

He was whispering to a dead man.

Mark crouched down in front of Leo.

He said nothing, simply looked him in the eyes and patted him on the shoulder.

***

That evening, after we returned home, Mark sat on the edge of the bed and stared at the floor for an hour.

"Leo doesn't have a father anymore," he whispered. "I have to get involved and be there for him. Sarah too. I have to make sure they're okay."

I nodded. "Sarah is going to need a lot of help."

"Leo no longer has a father."

A week later, he told me that Sarah had agreed to let him spend time with Leo.

"I'm going to take him to baseball practice every Saturday, starting this week," he announced.

And that's how the routine began. Every Saturday thereafter, Mark was at the door by 7 a.m.

"Training," he said, grabbing his keys with strange urgency. "Then I'm going to get her a hamburger. Maybe we'll do some other guy stuff."

All our friends and family started calling Mark a saint. Even I believed it. None of us suspected what was really going on.

Sarah had agreed to let him spend time with Leo.

One month after the start of this new life, I decided we could do more.

"Why don't you bring Leo here after practice?" I suggested. "I'll cook. Sarah must be exhausted. We can help her relax."

Mark stopped in the kitchen doorway.

"That could cause confusion."

"Sowing confusion about what?" I asked, genuinely perplexed. "It's just a meal."

Mark stared at the wall, thoughtful. Then, finally, he nodded in agreement.

"Okay. We can try."

"Why don't you bring Leo here after training?"

The first Saturday Leo came, the atmosphere changed instantly.

The boy stood in the entrance, his backpack pressed against his chest like a shield. It was as if he were waiting for permission to breathe.

We decided to make cookies, and afterwards I started reading Harry Potter to him. He was an adorable child.

Mark remained seated at the kitchen table the whole time, watching us. I could feel his eyes digging into the back of my skull. Every now and then, Leo would glance nervously in his direction.

The atmosphere changed instantly.

Last Saturday, training ended earlier than expected because of the rain. Mark drove Leo home, but he was in a terrible mood. He complained of a severe headache and said he had to go to the pharmacy.

The second the front door closed behind Mark, Leo changed.

His rigid posture disappeared, replaced by an intense, nervous energy. He sat down at the kitchen table, gripping a blue pencil so tightly that his knuckles turned white.

"You're not lying," Leo said in a low voice.

He was in a terrible mood.

It was so strange and serious for an eight-year-old to say.

I stopped what I was doing and stood in front of him. "I'm trying not to, Leo."

He glanced towards the front door to make sure Mark was gone. Then he reached into his pocket and pulled out a folded piece of paper.

"But Mark's lying. I wasn't supposed to steal that," he whispered, his voice trembling. "I took it from Dad's coffin. Before they closed it."

A chilling shiver ran down my spine.

"I wasn't supposed to steal that."

"Mark put it there. He slipped the note under Dad's hand. But I saw. I waited until he was gone." He pushed the paper towards me.

"It's serious. You should read it."

My hands were shaking so much that I could barely open the paper.

The first line chilled me to the bone.

"David, I need you to take this secret to the grave with you..."

My legs gave way and I sat down on the nearest chair.

"David, I need you to take this secret to the grave with you..."

I never wanted you to know, because it would only hurt you, but I love Sarah. I always have.

I never went through with it. I swear. I would never have done that to you. But pretending I didn't feel it almost broke me. Watching you build the life I had imagined, raise the son I would have given anything to protect...

I'm not going to try to replace you, but I will intervene, now that you're gone, to make sure they are never alone.

Forgive me for having loved what was never mine.