Rumpless welsummer?

[graphicali]

I have a couple of Welsummer chicks, 8 weeks old now. One still has no tail feathers at all. I will post a pic once it is light enough outside. Is it possible for a Welsummer chick to be rumpless. How common are defects like this?

 

[graphicali]

OK, here's a pic of Bumless George and his brother - who has a normal tail