I have just gone to feed my bunnies and i normally get greeted by both running out the shed into the run to me, but only Milo came

my stomach turned as i knew something was wrong

There is no reason for her sudden death and the only thing i can think of is shock of fireworks maybe??!! Could that kill a bunny??
They were totally warm enough with extra straw and the shed they live in has been plasterboarded.
I dont know how Milo will react to losing her also, as they were brother and sister and always together grooming each other and playing.
(sorry in tears as i write this)
RIP Lola you will be missed xxx