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On December 15, Song Il Kook uploaded the picture below on Instagram of Man Sae holding a letter he received in kindergarten with the caption, "Today! A charming Man Sae who brought home a love letter". 

The picture shows an adorable Man Sae with a mischievous smile, holding the letter he received, which says, " Song Man Sae oppa, let's play together. I like you".

Man Sae, Dae Han, and Min Guk are the triplets of Song Il Kook and were the former stars of the hit variety show 'Superman is Back'. Isn't he the cutest?

??! ????? ????(?) ??? ??? ??~^^; #songmanseh

A photo posted by 1958 (@songilkook) on Dec 15, 2016 at 6:29am PST