Archie Andrews half sister? Riverdale's newest member

Ally Andrews grew up far away from Riverdale in New York City, her dad being Fred Andrews estranged brother who was also at one point best friends with Hiram Lodge followed his best friend to New York City where he married his high school sweetheart and became a powerful rich business man, his wife also got pregnant with Ally who was only a few months younger than her cousin Archie. 15 years later the marriage has crumbled and then freds brother is gone leaving Ally alone with her mom, as ally begins to act out her mom decides to send her to live with her uncle whom she learns might not just be her uncle