Robert McGuire (ロベルト マクガイヤー Roberuto Makugaiyā) is Kitamoto's nephew. He is the son of Kitamoto's older sister and an American mainly living in the US, but sometimes he stays at Kitamoto's house. Shin calls him "Beruto-kun". Sometimes he plays with Shin-Chan and is let loose by the nonsense believing that they are Japanese customs. At first, he couldn't speak any Japanese at all so he would misunderstand everything and was naive to Japanese culture so he took everything Shin-chan would tell him about it at face value. Over time and with the help of Shin-chan, he learned the language and even gets to work as an English teacher in Japan at an eikaiwa school. In one episode he became interested in kendo and practiced in the dojo of Kenta Musashino.
He once had a crush on Nanako Oohara. Even though he is said to be half-Japanese, he still has the stereotypical Caucasian features- blonde haired, blue eyed, and a pointy nose.
In the LUK Internacional dub he is a Frenchman instead of an American.