I (31F) have a 6-year-old son.
And a younger sister (27F) who has always been… overly involved in his life.
At first, I thought it was sweet.
She’d show up unannounced with toys.
Offer to babysit anytime.
Even cancel her own plans just to spend time with him.
Everyone used to say, “You’re so lucky to have her.”
And honestly… I agreed.
Until recently.
About a month ago, my son started acting different.
Nothing obvious at first.
Just small things.
He became quieter.
Stopped talking about his day.
Started waking up at night.
Crying.
When I asked him what was wrong, he’d just say:
“I don’t want to go to auntie’s house anymore.”
That caught me off guard.
Because he used to love going there.
I asked why.
He just shook his head.
Said, “She told me not to tell.”
My stomach dropped.
I confronted my sister that same day.
She laughed it off.
Said he probably watched something scary.
Or had a bad dream.
And somehow… I let it go.
I shouldn’t have.
A week later, I picked him up early without telling her.
Her door was unlocked.
I walked in quietly.
Calling their names.
No answer.
Then I heard voices.
From the bedroom.
My sister’s voice…
Soft. Calm.
But not the way she usually talks.
She was saying:
“Say it again.”
A pause.
Then my son’s voice.
Flat.
Almost rehearsed.
“I miss you, Mommy.”
I froze.
Because I was right there.
In the house.
Alive.
Then she said:
“Good. Again. But this time… like you mean it.”
My heart started racing.
I pushed the door open.
And everything went silent.
My son was sitting on the bed.
Holding a photo.
Of me.
But… it wasn’t recent.
It was old.
From before he was even born.
My sister turned to me.
Smiling.
But there was something wrong with it.
Something… off.
I asked her what was going on.
She didn’t answer.
Just gently took the photo from my son’s hands.
And said:
“We were just practicing.”
I grabbed my son and left.
He didn’t say a word the whole way home.
That night, I went through his backpack.
I don’t even know why.
Maybe instinct.
And that’s when I found it.
A small notebook.
Not his handwriting.
Hers.
Every page had the same thing written over and over:
“Mommy left me.”
“Mommy didn’t want me.”
“Mommy is gone.”
Different dates.
Different handwriting styles.
Like she was teaching him.
Conditioning him.
I felt sick.
The next morning, I called my parents.
Told them everything.
And that’s when things got worse.
Because instead of being shocked…
They went quiet.
Then my mom said:
“She’s still not over it.”
I asked, “Over what?”
And that’s when they told me something I was never supposed to know.
Before I got married…
Before I had my son…
My sister was pregnant.
She lost the baby.
And according to them…
She never recovered.
They said she started calling my son hers behind my back.
That she thought if she spent enough time with him…
It would “fix something.”
I asked them why they never told me.
My dad just said:
“Because she seemed happy again… once your son was born.”
Happy.
That word didn’t sit right with me anymore.
I’ve cut off contact since then.
Blocked her.
Changed routines.
Even switched my son’s school pickup.
But yesterday…
I found something on my doorstep.
A small gift box.
No name.
No note.
Just one thing inside.
That same old photo of me.
And written on the back, in my sister’s handwriting:
“He misses his real mother.”
So now I’m stuck.
My parents think I’m overreacting.
They keep saying she’s “just hurting.”
But I can’t ignore what I saw.
Or what she was doing to my son.
So AITA for cutting my sister off completely…
Even if it means tearing my family apart?