Is it a small T-rex cousin, or is it just a baby T-rex?

Found in Montana’s Hell Creek formation, the Cleveland skull was originally classified as Gorgosaurus but later proposed as a new species, Nanotyrannus lancensis, due to its smaller size compared to T-rex. Whether Nanotyrannus is a distinct species or a juvenile T-rex remains contentious, with arguments based on cranial sutures and growth rates