This would be an interesting misdirect that could heavily change the dynamics of the series.
In related Prodigal Son news, Malcolm learned that his biological father is not the known serial killer (and his presumptive father), Dr. Martin Whitly.
Despite the twist-fueled lead-up to Season 2, the episode was surprisingly not intended to be the finale.
The twist led to Malcolm learning he may not be his father’s son (in terms of being a killer), but his sister may be his father’s daughter.