Estonia/Siberia is a fanmade pairing for fanmade a character for Hetalia: Axis Powers, involving the characters Estonia (Eduard Von Bock) and Siberia (Anastasia Charkova). This pairing is sometimes refered to as EstSib, a portmanteau of their respective names.
During the time of the Soviet Union, Eduard grew to have feelings for Anastasia but he kept them to himself, possibly because he was afraid of how Ivan would react. Although it seemed Anastasia returned his hidden feelings.
Eduard and Anastasia have been married since 1993 and are still happily married. Although they are happy, it seems Anastasia may have strong romantic feelings for Ivan. It is hinted that Anastasia maybe pregnant with Eduard's child.