Jessica celebrated her younger sister Jung Soo-jung's birthday. On October 24th, Jessica posted several photos on her social media account with the message, "Happy birthday to my favorite puppy."

In the photos, Jessica and Jung Soo-jung are standing side by side leaning against a wall, showing off their superior proportions. The two attract attention with their similar appearances, and in another photo, they are seen holding hands while walking down the street. This shows their affectionate sisterly bond.

Jung Soo-jung was born on October 24, 1994, and is 31 years old. She debuted in 2009 as a member of the group f(x) and is active as a singer and actress. Jessica debuted as a member of Girls' Generation but left the group and continues to maintain global popularity by managing a fashion brand and music activities overseas.

Jessica added, "Happy birthday, my favorite puppy. Stay cute and quirky. Don't touch my donut," celebrating Jung Soo-jung's birthday. In the released photos, the two pose in front of a red brick background or walk holding hands, capturing their affectionate sisterly daily life.

Jung Soo-jung matched a cream-colored knit with navy shorts and loafers, creating a neat yet refreshing atmosphere, while Jessica completed a natural yet sophisticated style with a checkered shirt and denim shorts. The two showcased a similar look with white socks and vintage items, revealing their sisterly fashion sense.

In the following photos, Jessica is also seen taking a mirror selfie while celebrating Jung Soo-jung's birthday. The number "31" is written on the back of Jung Soo-jung's leather jacket, symbolizing her 31st birthday. Jessica boasts her still superior visuals, and Jung Soo-jung responds with a cute smile.

Fans showed various reactions such as "The real sister chemistry is the best," "Both are so pretty," "Even their fashion sense is alike," and "As Jessica said, no donuts allowed!" Jung Soo-jung is currently active as an actress, and Jessica continues her fashion brand and music activities overseas. Both are successfully active in their respective fields and continue to maintain their bond as sisters.