During an interview with Tenasia, Jessica talked about how supportive sister Krystal was for her solo album, 'With Love J'. She said, "Krystal is the one who was most excited when I was preparing my solo album. When I was trying to pick my title song, she gave it a lot of attention to the point where I got a bit annoyed." 

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She continued, "She even picked the release order of my teaser images, and came to my MV set and watched me like a director with her arms crossed. She showed me in action rather than in words, and helped me by my side." 

Jessica then added, "Songs might leak so I didn't send it to Krystal, but she kept asking for it. I didn't send it to her until a few days before my promotions in China. She kept bugging me because she wanted to hear it first." 

Lastly, Jessica talked about a possible duet with her sister and said, "We share a lot about music. A duet is something we've always considered."