How to do this? (Make a character do a animation while another character is talking)

Hey guys, So I wanna make my character, Emma to stop her animation while Sarah is talking. When i do @EMMA is (animation) there is a pause before the other character talks. I’ll show some photos too.

Please tell me how I can make Emma go into a different animation when Sarah is talking.

&EMMA is animation
SARAH (talk_…)
dialogue