A geep is half a sheep and half a goat. You don't see them very often, but there was one born on a farm in Ireland a couple of weeks ago. This wasn't planned - it seems that the goat managed to get mixed up with the farmer's herd of Cheviot sheep and bred with one of the ewes. As you can see from the picture, at the moment it looks mainly like a lamb with a rather funny face (not sure if the young animal should be called a lamb or a kid though - or maybe a lid?)
Goats do occasionally mate with sheep, but usually there is no offspring, or if there is any, there is a high chance that the young animal will be stillborn or the mother may not survive the birth. So a healthy geep born to a live mother is a rare event. According to the farmer this one is very lively and seems to run faster than the other lambs on the farm.