Craig Bowker Jr boards the Hogwarts Express on Platform Nine and Three-quarters at King’s Cross to start his first year at Hogwarts. He is surprised that a Potter is sorted into Slytherin (CC1.3), although it is unclear at that point which house he has himself been sorted into.
Craig is found in the Hogwarts Library doing the Scorpion King’s homework for all of his classes, so this makes it likely he is also a Slytherin as well (CC3.4). Later on, he also tries to prevent Ginny Weasley and Harry Potter from entering the Slytherin dormitory to look for their son Albus (CC3.15).
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Pottermore: Harry Potter and the Cursed Child
The theatre production opened in the West End of London at the Palace Theatre on 30 July 2016, with Jeremy Ang Jones in the role of Craig Bowker Jr: Harry Potter and the Cursed Child, Parts One and Two