Sean Smith was a pre-War American citizen who was accepted into Vault 114.
Living before the Great War, Sean, his wife Molly, their son Paul and infant daughter Stephanie were all designated to live in Vault 114. Their family, the Smiths, were assigned to the Residency B2 section of the vault. However with Vault 114's unending construction they may not have been there when the bombs hit Boston.
Sean Smith is mentioned only in Fallout 4.