Chapter 7
Since that day, Mom had restarted the overseas math journal subscription she'd canceled after getting her master's degree.
Strictly speaking, it was because I'd nagged her into restarting it.
On the day each new issue arrived, I woke up early and waited by the front door for the delivery man.
“Delivery man! Thank youuu—!”
“Goodness, what a polite little lady. You're welcome.”
I grabbed the envelope and dashed to the sofa, then spread it out.
Ah, look at this radiant sheen.
Research papers on all sorts of problems across fields like complex analysis, combinatorics, algebra, and topology, gathered together all at once.
To me, this is the One Piece!
“Mom! Mom! The new issue for this month is here!”
When I bounced in place, excitement practically spilling out of me, Mom sat on the sofa with a helpless look, and I nestled into her lap.
This became our routine.
If I came across a part of a paper Mom didn't know and skimmed over it, I pretended not to know and asked about it.
“Mom, why do we need this condition here?”
“Hmm... hold on.”
While Mom thought it over, I waited, swinging my feet back and forth.
'Yes, yes. Almost there.'
“…Ah! Without this condition, it won't converge later.”
“Ohhh—!”
I clapped my hands, clap-clap-clap.
Mom looked at my expression for a moment, then let out a snort of laughter.
“Why are you even more excited than A-yeon?”
“Nihihi. I'm happy Mom figured it out!”
Well, naturally...
Mom didn't think I would truly understand these papers properly.
Instead, because all the reasoning in those journals was written in English, I spent the time practicing listening by hearing Mom's English pronunciation, while Mom studied the math she'd set aside for a while.
You know how these days parents even read English picture books to little kids, right? It felt a bit like that.
But whenever I asked about something I was curious about, Mom would think it through carefully and answer sincerely.
That was enough for me.
✒️✒️✒️
About four months passed.
During that time,
the books in the upstairs study were gradually being brought down to the first floor, where my little hands could reach them.
The newspapers and journals Dad bought kept piling up too.
Math, physics, chemistry, biology, economics, engineering.
The fields were all different, but I devoured them without discrimination.
The more knowledge I crammed into my head, the hotter it got.
The sensation of explosively growing synapses connecting, connecting, and connecting again.
I could feel it in my body—at this age, synapse density really was at its lifetime peak.
'Good. I won't waste even a second of this golden time.'
I decided to add one more routine to the mix.
Multilingual skills.
Right now, with my brain growing explosively, this was the perfect time to learn languages.
Language, too, is something best learned at this age, when it gets etched deepest into you.
Chinese, Japanese, French, German, Spanish.
Should I just start with this much for now?
Fortunately, when I used to go around attending overseas conferences in my past life, I'd already studied these languages to a basic conversational level.
Now I just had to flesh it out.
I tugged at Dad's trouser leg.
“Dad. Dad.”
“Mm? What's up, sweetheart?”
“Can you buy this for me?”
I carefully wrote it down on a memo and handed it over.
[Chinese Conversation, Japanese Conversation, French Conversation, German Conversation, Spanish Conversation]
They were conversation books that even came with MP3 files, so you could practice speaking and listening. I picked them out myself.
Dad took the memo and read it once, then again.
“…Our daughter?”
“Yeah?”
“Do you really need all of this? Seriously?”
“Yeah!”
I nodded vigorously.
Dad glanced at Mom for a moment.
Mom gave a slight nod.
“…All right. I'll buy them. But still, our A-yeon, aren't you getting smart way too fast? Dad's starting to feel jealous.”
“Hehe~ Then Dad should study with me too!”
“Hmm... should we? Want to study English together?”
“Okay!”
All right.
Mom and Dad had both been successfully roped into my study viral-marketing campaign.
Teaching Mom math and teaching Dad English. I'm such a filial daughter.
✒️✒️✒️
Yoo Arin, 11 months old.
While I was reading a conversation book in the living room, I noticed something.
Mmm-mmm-.
Arin was moving her lips.
“Gasp...!”
Having personally experienced this just two years ago, I knew it immediately.
This was definitely her first-words milestone!
A baby's first word.
From a language-acquisition standpoint, it was the sign that the brain's Broca's area and Wernicke's area were beginning to connect.
Input and output were starting to form a circuit.
But the first thing I thought of at this important moment was this:
'I want to hear Arin call me unnie first...!'
I wanted Arin's first word to be "unnie."
More than Mom, more than Dad.
I, Yoo A-yeon, wanted to be the first person Arin called.
Such a simple, clumsy desire.
A desire a child might have.
But since I'm actually a child, that should be fine, right?
I closed the conversation book and crawled over to Arin.
Then I sat down in front of her and made eye contact.
Arin saw me and smiled brightly.
“Arin, repeat after me. Unnie.”
“Awoo-.”
“No, look carefully. Unnie.”
“Woo-woo-.”
As expected, it wasn't easy at all.
'ㄴ' is a tongue-tip sound.
It's a sound made by placing the tip of the tongue precisely behind the upper gums.
A fairly difficult move for a baby, since you have to lift the tongue muscles upward.
By contrast, 'ㅁ' and 'ㅂ' are lip sounds.
Since they're made by just bringing the lips together and opening them, they're nowhere near as hard as 'ㄴ'.
Besides, because they use muscles like the instinct of suckling milk, the very first sounds babies usually master are lip sounds.
So statistically, the first word Arin could easily blurt out now was overwhelmingly likely to be either "Mom" or "Dad."
It was a matchup with overwhelmingly low odds from the start.
But.
'I don't want to give up just because of that.'
Because I'm Arin's unnie...!
I grabbed Arin's soft cheeks with both hands and squeezed them.
“Huh?”
I locked eyes with her.
“Arin, unnie, unnie, unnie, unnie...”
And then I kept feeding Arin the word unnie endlessly.
Dad poked his head out from the sofa at the sight.
“Sweetheart, what are you doing?”
“Sorting out the hierarchy so Arin knows who the older sister is.”
“Puhaha, what's that? Teaching her to say unnie?”
Dad quietly came over and crouched down.
“But 'ㄴ' pronunciation will still be a bit hard for Arin. That sound usually comes out around the first birthday, give or take. She still has a month left.”
“Yeah... but...”
Dad glanced over at Mom.
Mom also chuckled and shook her head.
“A-yeon, Dad's right. Rather than forcing it, it's better to wait naturally—”
“Hing... but it won't work...”
I pouted, pushing out my lips a little.
“I want Arin to call me unnie first...”
I said, biting my index finger.
Then my parents exchanged glances and snickered, silently signaling to each other.
“Really? Then we'll cheer A-yeon and Arin on. Fighting.”
I kept making eye contact with Arin and gave her personalized one-on-one tutoring.
“Unnie. Unnie. Look carefully. You lightly touch the roof of your mouth with your tongue like this. Like this—ahhh—”
I opened my mouth and exaggerated the shape of my tongue tip touching the upper gums.
Whether she knew it or not, I was working hard.
“Heehee!”
Arin only burst into laughter after seeing my open mouth.
✒️✒️✒️
The next day.
The day after that.
And the day after that, too.
I sat in front of Arin whenever I had a spare moment, without even reading books.
“Unnie. Unnie. Unnie.”
Arin stared at my mouth and moved her lips.
“Uh... uhuh-.”
I could feel a 'ㅁ' trying to come out.
The most natural motion was to bring the lips together and then open them.
“No, it's not 'ㅁ'.”
Aah-.
I opened my mouth even more slowly and showed her the shape.
The movement of the tongue tip rising upward.
“Un-nie.”
Arin's eyes followed my mouth.
“Uh... uhuh...”
“That's right. Tongue up.”
And then.
From Arin's mouth.
“N...”
“…!”
At that moment, I held my breath.
“N... nuh...”
“Yes, that's it! Good job!”
As I clapped with delight, Arin also realized that was the correct answer and kept moving her tongue, practicing the 'ㄴ' sound.
I continued the one-on-one special training with Arin for over thirty minutes.
And finally.
“Ni... unnie-.”
When the word I'd wanted so badly came out of my little sister's mouth, I felt like I was about to shoot into the sky from sheer happiness.
“Great job! Our Arin is the best!”
I hugged Arin tightly.
Arin grinned brightly.
“Heehee, unnie-!”
“Yes! I'm your unnie! Arin's unnie!”
✒️✒️✒️
“Honey, look at that.”
“Mm... I see it.”
Han Seol-ae and Yoo Jin-ho were hiding behind the wall, secretly watching the sisters.
At the same time, they were filming a video on their phone.
For several days, she'd even set aside the books she loved and done special training with Arin, and in the end, she succeeded.
“Seriously, her determination is amazing. Definitely our daughter.”
The couple did cheer A-yeon on, but honestly, they never once imagined the 'ㄴ' sound would come out before the 'ㅁ' and 'ㅂ' sounds.
Usually, sisters two years apart don't get along very well.
As they grow up, they invade each other's territory and fight over their parents' attention.
But Yoo A-yeon gave up the books she liked and spent time with Yoo Arin.
Something impossible without love.
Han Seol-ae and Yoo Jin-ho thought those two would definitely keep getting along well.
✒️✒️✒️
That night.
I lay in bed, staring at the ceiling.
I was too excited to fall asleep easily.
Wriggle-wriggle-.
'Unnie.'
The first word Arin had ever uttered.
Not Mom, not Dad, but unnie.
'... Was it this good a feeling?'
Even though I'd been going around calling myself my little sister's unnie, actually hearing the word unnie come out of my little sister's mouth felt entirely different.
Heeheeheehee.
Flap-.
I pulled the blanket all the way up to my head.
And I smiled to myself without letting anyone catch me.