Sorry for being a little late
, have been bussy.... but this other tread is good for the matter.
Sample Size Does Matter
On that post, I try to say, you can calculate with almost any sample size but, the important thing is What is the worst case value for such estimate. Maybe many of us like to show good numbers, but being real is important, and most of us take the estimates as the true value, not just an estimate.
There are other issues far more important than sample size, as is stated on this tread, the normality is the real deal, and sample size does not assure the Gaussian Distribution.