Hogget for in between.
A sheep in its first year is a lamb and its meat is also lamb. The meat from sheep in their second year is hogget. Older sheep meat is mutton.
Oh.., maybe not.
Generally, "hogget" and "sheep meat" are not used by consumers outside Norway, New Zealand, South Africa, Scotland, and Australia.
Rh-null. So rare they can almost never receive a transfusion.