According to an article that appeared in People in 2010, this horse 'Einstein' has a big personality."The horse, who weighed just 6 lbs. at birth (the world's smallest newborn horse, Thumbalina, weighed 9 lbs.) may be diminutive in size, but his personality is super-sized." Even Oprah got to meet Einstein! He's SO adorable. It's said that the chances of an 'Einstein' being born is one in a billion.