What happened to Sowon and Yerin in the past?

Yeso Sisters' path to school is difficult.

소원

Haam~ I slept well!

소원

Lin, wake up, it's 7 o'clock!

예린

Yeah~~haam~

예린

I slept well!

엄마

Yerin Sowon, eat

Yerin, Sowon: Yes

소원

It's fun!

엄마

Really? Eat a lot

엄마

By the way, why doesn't our child eat?

예린

What is this side dish!

예린

I'm not eating!

엄마

Yeah, don't eat it!

예린

Huh! (sob)

Yerin Sowon: I'm going to school.

지성쌤

Did your wish come true, Yerin?

소원

Lin? She must have gone to the store.

지성쌤

this

예린

hello

지성쌤

Why are you here now!?

예린

Did you go to that store?

지성쌤

What time is it now!

예린

It's 9:30 now.

지성쌤

Where is this rebellion against the teacher!

지성쌤

I'm standing behind you with my hands up!

예린

yes

해설자

Break time has come

엄지(일진)

Hey, if you want, I'll give you 100 won, so buy some bread.

소원

No! You have no hands and no feet.