Song Ji Hyo, Jang Yoon Joo, Sunny, & Red Velvet's Seulgi spotted filming at 'Lotte World' in school uniforms

According to netizens on October 24, Song Ji Hyo, Jang Yoon Joo, Girls' Generation's Sunny, and Red Velvet's Seulgi were spotted filming at 'Lotte World' amusement park!

The 4 female stars were spotted dressed in school uniforms, wearing adorable animal headbands and enjoying their time, not paying mind to the fans and the public surrounding them. 

Netizens commented, "Is it 'Pajama Friends'?", "Sunny looks like a baby", "'Lotte World' today?! Why wasn't I there??", "Seulgi is really shining, especially with her hair dyed", and more. It seems many are guessing that the filming is related to currently airing reality series 'Pajama Friends', judging by the presence of Song Ji Hyo and Jang Yoon Joo. 

Who would love to go to the amusement park with these 4 lovely female stars?