A Trap

Instead of taking every step in the staircase, Aidan was skipping two steps and taking the third one. This means he was climbing the stairs with a run and jumping over a few steps.

Indeed, he was angry and was ready to tear Hailey apart. 

Aidan was furious because of how badly Hailey was treating everyone in the mansion, yet she has the nerve to bring her younger sister to torture the household together. That can't be possible.

He remembers when he came back home on a fateful day and he was informed by one of the guards that Hailey's younger sister, Kate, came to the house and almost caused trouble. 

If not because Hailey was still pretending to be nice to Ruby at that time, only God knows what would have happened.

On his way to his room, Aidan met Ruby climbing down the stairs to the living room. She heard Aidan's voice from her room and she was coming downstairs to welcome him.