Cecotropes can most definitely stick. I think Suzette, you might be talking about diarrhea or runny poop that isn't "normal" but night droppings are moist, sticky poops that have potential to get caught and stick to fur.
So, to Mary...sorry if this is confusing. But the article posted is a must read for you. Your buns were weaned too early and there is the possibility that the poop issues you are describing are because of that. I don't mean to trivialize Suzette points at all because runny poop issues can be VERY dangerous to young buns.
With that being said, I have had very similar issues with nigh droppings with Agnes when she was a baby. Personally, I think it was simply a combination of her age (young buns don't know what is good for them yet, they might not eat all their Cecotropes) and also just her personality. I posted a thread on here about night droppings and found out that some owners see them all the time from their rabbits, some never do.
Now, too many uneaten Cecotropes can indicate a diet problem, but in Agnes's case it wasn't. She is over it now, I only see a night dropping every now and again.
So, to again reiterate, read that article and make sure you are educated on signs of a baby being weaned too young and could be in danger. But also know that if bunny seems okay in all other areas, it could just be night droppings too.
Phew! Sorry this is so long
I might not be explaining myself good. And not meaning to cancel out what suzette is saying too. Very good info