I never thought Amy could be a Princess, but I have three points for how she could be a princess.
1: 'Princess Sally Acorn and Amy Rose confusion', Amy was called 'Princess Sally Acorn' at one point... Was Amy supposed to be a Princess at one point? - Sonic tagahanga base
2: 'King Rob O' the Hedge', is Amy's cousin, apparently, Rob doesn't have any siblings, so if Rob sinabi no to the crown, that would make Amy royal. And would have meant that she wouldn't have met Sonic, because she had to learn the royal ways if she was going to became Queen. - Sonic comics owned sa pamamagitan ng Archie and SEGA
3: In 'Knights if the round table' Amy was 'Lady of the lake'. She looked part royal, and she seemed to know what was wrong with the King... Was she once a Princess or lived in the kastilyo at one point? - Sonic game owned sa pamamagitan ng SEGA
You decided in the comments if Amy is 'Princess Amy Rose' or not.
