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(Japanese: レイ Rei) is a character of the day who appeared in JN037. He is the son of Professor Kukui and Professor Burnet.
In SM146, it's revealed that Burnet was pregnant. When Ash returns to Alola, Rei first appeared when Burnet opened the door to her families house and reunited with Ash and Pikachu. Although he is meeting Ash for the first time, Rei is very receptive to Ash.