Toddlers bedtime?

jane
My sister in law has a 16 month old and we were talking about when my LO and hers go to sleep. I said my LO falls asleep around 8:30 sometimes 9 and usually wakes up around 9. She looked at me and said "isn't that early?" I said I didn't think so, but she went on to tell me about how her 16 month old doesn't go to bed till 11 sometimes midnight and doesn't wake up till 11:30 or noon.  I didn't say anything because I didn't feel as if it was my place, I just can't help but thinking that's awfully late to bed and late to wake up. What do you ladies think?