I think this graph tells you everything you need to know. https://books.google.com/ngrams/graph?content=baby+sheep%2Clamb&year_start=1800&year_end=2010&corpus=1

I think this graph tells you everything you need to know. https://books.google.com/ngrams/graph?content=baby+sheep%2Clamb&year_start=1800&year_end=2010&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cbaby%20sheep%3B%2Cc0%3B.t1%3B%2Clamb%3B%2Cc0 https://books.google.com/ngrams/graph?content=baby+sheep%2Cl...