The character that represents the country, Estonia. He is the second eldest of the Baltics (Lithuania being the oldest) and a subordinate of Russia.
He is probably the smarter and luckier of the Baltics since he can escape Russia's attacks. He doesn't mention anything that would upset Russia, and if that fails, he makes up an excuse to leave. An example of this is when Latvia unintentionally mentions that the other countries would call Russia a "drunkard" or "frozen Frenchman" in Russia's presence, so Estonia leaves to make tea. Lithuania then comments about how Estonia ran away without them.
When the Latvia cries over relying on Russia, he states that he wants to try not relying on any country and wants to find his own way. He also mentions that the Baltic "countries" don't feel like "the three Baltic states" at all as the three had dinner and chose to eat different foods. They are "all over the place", and quite frankly, not very unified.
When he sees how Russia acts around his sisters, Ukraine and Belarus, he comes to the conclusion that Russia takes his stress out on the Baltic states because the two girls make Russia gloomy. Despite knowing this, he decides that having siblings is nice. It is likely that when Latvia says that he wants siblings, Estonia decided to play along with him and acts as his "older brother".
Other than the other two Baltics, Estonia appears to have a good friendship with Finland. The country stopped by to visit him after fleeing Denmark's rule with Sweden. Although, this ended with Sweden acquiring partial custody of both Estonia and his "younger brother", Latvia.