(T/N: the post is a big screenshot so we'll translate the text)
For reference, I only have a male dongsaeng and I've been envious of kids with sisters ever since I was small.
No matter how much you guys fight to death and curse at each other, in the end, you will never let your unnie or dongsaeng get tormented by other people. When I talk with my friends, the kids who have sisters would always talk about their sistersㅋㅋ since they stuck with each other for a long time.
I told my high school classmate that I was so jealous that they have an unnie but she said that she totally hated her unnie.
She said that I should take her unnie with me but now that we're past our 20's and we're in our 30's, and that marriage is right ahead of her, she said that if she has children, she would definitely have sisters.
She said that even if they fight, being sisters is the best...ㅋㅋㅋㅋㅋ
Just looking at my mom and aunt, when my grandmother on my mom's side passed away, I could feel how my aunt was like a mother, a friend and a parent. My mother and my aunt relied on one another and shared their concerns with each other and they had an unique relationship. Even if I'm her daughter, I'm so jealous of my mom for having an unnie..
No matter how close you are with your friends, you have worries that you're unable to tell others because of how embarrassing it is. I'm jealous at the fact that there's someone you can tell all your worries with without regards to your pride...
I think that no matter how close you are with your brothers, it will never be a relationship with sisters.
I think that there's a bond that's created based on relating to other women that cannot be created with men.
Of course, not all families are like this and there are sisters who even more like enemies than other people but in most situations I witnessed, the more I grow up, the more I realize that having a sister is the biggest luck and I'm jealous.
I think that I can only share about my embarrassing sides without feeling shame with my sister
I think that the only people who can be happy for your happiness and success without being jealous, and who will sincerely wish you a good life and who will care and comfort you are your parents and sisters.
Seriously, I'm so jealous. I wonder what kind of luck you have to sow in your previous life to have a sister.
Right now, I need a lot of comfort in my life so I'm even more jealous..... ㅠㅠ
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OP also has a sister and I'm happy. We talk on the phone for 1-2 hours every day
original post: here
1. I also have a dongsaeng and I love her so much ㅎㅎㅎㅎ
2. F*ck, my sister is such a trash
3. Having sisters is good. The closest person in the world to me is my unnie. Our personalities are different but she's seriously nice, responsible, strong and gives me good allowances. I wonder when I can repay her ㅜ
4. Being the only daughter is jjang
5. I also wanted a little brother or an oppa when I was young but now, if I gave birth to a girl, I would make sure that she gets a sister instead
6. We used to fight a lot when we were young but now that my dongsaeng got married and I got a nephew, we became best friensdㅋㅋ
7. Our unnie is the best♡
8. If you look at sisters who have a good relationship, there's always one side who gives unlimited services while the other side only receives. I've seen a lot of sisters developing jealousy once they get married and have children. It's common for kids to show off that they have sisters. Stay away from kids who have sisters
9. I have both a little sister and little brother and I like it ㅎㅎ
10. Am I the only one who hates my unnie? I don't even talk to her
11. ㅎㅎ I'm looking forward to the future.. 
Unnie, let's live happily
12. My dongsaeng is the best♡ I love you
