I wondered that, too. The character shows up out of nowhere and does something that would not seem to align with his father's motivations.mandevilleag said:
So why is the Hand's gimp son fomenting discord in the king's house. I can't tell if he is aligned with the Hightowers, but he certainly placed the seed of doubt in the queen's mind and continues to egg her on. I'm probably forgetting something from earlier in the series, but his father and brother don't seem disloyal.