Axel and Ghost were lovers until one day Axel suddenly died in action when a mission went wrong

Today marks two years since Axel died and the team finds themselves on a mission in the same area, Ghost stands there looking at the exact area he saw Axel die and starts to lose himself in the moment and suddenly lets out a whistle (this is how Axel and Ghost would communicate in combat)

suddenly there is a whistle back and everyone looks around in shock

Soap: it cant be Axel,he was KIA!