I may try to construct a sample to see if I can recreate this, do you know the number of observations, i.e., sample size?

I played around with a sample of {2,5,5}.

I got the sample mean to be 4 and the st deviation to be which is close.

That's about the highest st deviation I can get with a mean of 4 and a small sample.

Maybe with 2 observations I might get a st deviation of 2, but 2 is high.