Sonia Acorn

Sonia Hedgehog is King Sonic's and Queen Sally's daughter from the future timeline known as Mobius: 25 Years Later.

Unaltered Timeline
Sonia was born the daughter and first-born child of King Sonic and Queen Sally, and elder sister of Manik the Hedgehog. Sonia bears great resemblance to her mother, though she has inherited her father's super speed. Sonia has slightly more tolerance for her royal duties than her brother, which includes frustration because Manik, as first-born male, is heir to the throne of Mobius.

Altered Timeline
Following the timeline altercation by King Sonic, both Sonia and Manik ceased to exist due to their mother marrying Shadow in this timeline to keep him from destroying Mobius. After Shadow's defeat by Lara-Su, Sonic and Sally deside to get married and were already talking about children, indicating that Sonia and Manik might be born at a later point in this timeline.