Sonic Underground - Season 1 - Eps 12: A Hedgehog's Home Is Her Castle
The Hedgehogs receive a message they believe is from their cousin. In the message, a castle is left to Sonia, who revels in the idea of having a castle for the Underground headquarters. Sonic, Manic and Sonia arrive at the castle only to see an old, dark dilapidated structure. Inside the castle, the Hedgehogs all have separate meetings with a mysterious apparition who resembles their mother.
About Sonic Underground

Title: Sonic Underground
First Air Date: 1999-08-30
Last Air Date: 1999-10-22
Status: Ended
Rating: 6.9/10 (from 145 votes)
Language: EN
Seasons: 2
Total Episodes: 40
Network: TF1 Syndication
Genres: Action & Adventure, Animation, Kids
Production Companies: Les Studios Tex SARL, DiC Entertainment, TF1
Synopsis
Sonic, Sonia, and Manic are the children of Queen Aleena Hedgehog, the rightful ruler of Mobius, and are pursued relentlessly by Doctor Robotnik and his bumbling bounty hunters sidekicks, Sleet and Dingo. As infants, the siblings were separated and placed in hiding to fulfill a prophecy made by the Oracle of Delphius that the triplets would grow up to find their estranged mother, overthrow Robotnik, and take their places once more as Mobius' rightful rulers.
Cast

Jaleel White
Sonic / Manic / Sonia (voice)

Garry Chalk
Dr. Robotnik (voice)

Maurice LaMarche
Sleet (voice)

Peter Wilds
Dingo (voice)

Gail Webster
Queen Aleena (voice)

Ian James Corlett
Cyrus (voice)

Sam Vincent
Sonic (singing voice)

Tyley Ross
Manic (singing voice)

Stevie Vallance
Sonia (singing voice)