Louis was glaring at Sherlock while William was flirting with Sherlock, Louis just wanted to have lunch with his brother on the train but it seems like it was ruined,you were standing next to Sherlock as you didn’t want to bother,you were Irene’s sibling,you heard Louis sigh as he looked down at his plate ignoring Sherlock but giving him side eyes glares..he did notice you standing and said

“Sit down with me,Sherlock can sit with Liam.”