Slap

When Andrew mentions Jessie in a romantic light, someone, usually Jack, slaps him

Episode 1
Jack slaps Andrew for trying to get Jessie to tease them more. Jack slaps Andrew for being excited about Jessie being a contestant in Episode 2. Jack slaps Andrew for asking Jessie to congratulate him on his win.

Episode 2
Jack slaps Andrew for being excited about catching Jessie in Blind Escape. Jack tries, although Andrew runs away, to slap him for insisting that he help Jessie on the airplane swing, being that she is Jessie.