This is gaining a lot of traction on Pann and TheQoo.
Original Pann Post (please check directly since my translation isn't 100% correct) - https://m.pann.nate.com/talk/358126178
April's ex-member Hyunjoo left the group on October 29th 2016. At the time, the company said that she left to focus on acting, but according to her younger brother, that absolutely wasn't true.
According to him, Hyunjoo was bullied by the then members of April (Chaewon, Naeun, Yena, Jinsol) so badly that she developed panic disorder and eventually even tried to commit suicide.
The other April members apparently pushed for Hyunjoo to leave. Hyunjoo wanted to because of the bullying and her company told her through a letter to say she left to focus on acting, which she did word for word.
Hyunjoo's younger brother didn't want to bring this up earlier because it might harm Hyunjoo's image who resolved to focus on acting after her departure. However, he hates that the April members are doing well now without even apologizing for the pain they caused Hyunjoo. He details a time when his mother went to visit the company and the members just laughed when they saw her.
He says his patience has worn thin and hopes that the April members no longer appear on TV and remind his sister and parents of all the abuse she suffered at their hands.
The original post has proof that he's her younger brother. Fans have asked him to post Katalk messages and the company's 'pressure letter' to Hyunjoo forcing her to leave and he said he will. He did post proof of another document though I'm not too sure what it is.
EDIT: Allkpop article with translation - https://www.allkpop.com/articl…nt-where-she-got-suicidal
EDIT 2: I edited some parts that were incorrect translations.
UPDATE: DSP Media is now 'checking the facts' - https://theqoo.net/index.php?m…l&document_srl=1866988754