Bunny’s average lifespan?

I made a post about losing my baby girl and have gotten so much support, for that I am grateful. But, I am starting to wonder, at what age do bunnies usually pass? My baby would’ve been 6 in September. Is that young? She was a big breed, bigger than my cats. But I’m not sure if it was odd or normal for her to suddenly pass in her sleep at that age.