Disney's Descedants: Return of Maleficent favorite child

Mal was thinking about the time she was a child and how she and her older brother did everything together steal, lie, cheat (any bad/evil thing you can name or think of they did it) and now she's going to auradon without him..or is she, luckily for Mal her brother managed to hop a ride on the limo to auradon, but when it comes down to making the decision of a lifetime will he be good with his sister or remain evil like his mother