Miss Edna is a "Miss Nanny" type robot who assists her owner, Mister Zwicky in running the Schoolhouse at Diamond City. Miss Edna was programmed to speak in a French accent and may have also been a product of emotion-sensing experiments. Her love for working and being with Mister Zwicky for a long time has heightened her bond with him, allowing her to start developing deeper feelings.
If the Sole Survivor responds to Miss Edna's questions by promoting the importance of "love", Miss Edna will ask them if it's possible for two very different people to experience love towards one another. If the player agrees that it's possible, Miss Edna will thank them for their insight. Later, upon a subsequent return to Diamond City, one can witness Pastor Clements wedding Miss Edna and Mister Zwicky in the road, across from the entrance to Publick Occurrences. The ceremony is rather brief and may be almost over depending how quickly the Survivor finds them, so be sure to seek this out or one will miss it as it's easily mistaken for background noise as they don't have a crowd. Pastor Clements can later be heard saying that he thinks the marriage of a man and a robot is strange, but he doesn't think God would mind.
Miss Edna only has pincers for her three hands instead of a saw or ranged weapon.
Most "good" companions like Piper, Curie or Deacon will like or even love if the Sole Survivor supports Miss Edna in realizing her feelings for Zwicky. Conversely, more rude or selfish characters like Cait won't take kindly to it at all.
MacCready and Strong like telling Edna that children need love and encouraging her to share her feelings with Zwicky. However, Strong dislikes the following speech options: 'that love conquers all / cannot be bothered by love.'
Miss Edna's voice is similar to Curie's, another Ms. Nanny robot. This is because they are programmed with the same voice. Codsworth and other Mr. Handies are similar in that they also all share the same (masculine) voice.