Jessica congratulated Krystal on her birthday with sweet posts!

On October 24, Krystal celebrated her 23rd birthday. In celebration, her older sister Jessica dedicated the cutest Instagram stories. 

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The first story showed a goofy selca of Jessica and Krystal. 

Jessica added a sweet note, saying, "Happy Birthday darling", on the second story. 

Last but not least, the third story showed Krystal giving her sister a manicure. The caption reads, "Happy Birthday!"

These two are definitely sister goals! Happy Birthday, Krystal.