He was sentenced to a term of 15 years, with a review after 8, last month.
An appeal against conviction has been lodged by Boy B in relation to the Anna Kriegal Murder case.
Boy B was accused of luring the 14-year-old schoolgirl from her home in Leixlip to a derelict farmhouse in Lucan where she was killed last year.
The now 15-year-old was sentenced to 15 years detention for his role in her murder, but his sentence is to be reviewed in eight years.
At last month’s sentence hearing, the court heard he doesn’t accept the verdict and his lawyers have now lodged an appeal against his conviction.
There’s still no word on whether Boy A intends to appeal his conviction and/or sentence.