Conversation so far:
What happened in 2008?
group was scheduled to have their comeback in March 2008 with their second album, however, member Kim Sung-hee suddenly announced that she would be leaving.
why did she leave?
parental pressure because her participation in the group was contingent on the maintenance of her grades.

Question: did they have a replacement?
Self-contained rewrite: did Kim Sung-hee have a replacement in Kara?