As to the matter whether Emperor Chokei and Emperor Gokameyama were brothers, there is no evidence to prove it and most people denied it, however there are some scholars like Hokiichi HANAWA who claimed that these Emperors were brothers from early on (according to HANAWA, Emperor Gokameyama was an older brother and Emperor Chokei was a younger brother).
他方、長慶天皇と後亀山天皇が同母兄弟なのかに関しては、それを裏付ける確証がないことから否定的な見方が有力であった中で、塙保己一のように早くから同母兄弟であることを主張する人もあった（ただし、塙は後亀山天皇を兄、長慶天皇を弟と主張していた）。