The photographer and his wife.
Backward text in some correctly-scanned photos is discussed in this post on Patreon: https://www.patreon.com/posts/46066525
Double exposure in camera
Taken from the top of Mt. Constitution, Orcas Island, WA.
Taken from the top of Mt. Constitution, Orcas Island, WA, looking toward Lummi Island.
This appears to be the Commandant's House at Fort Simcoe Historical State Park in Washington State (US). Further details on Wikipedia: https://en.wikipedia.org/wiki/Fort_Simcoe
Apparently an in-camera double exposure (this was just one slide).
According to @SeattleParks on Twitter, the photos in this set were taken in 1955. Ref: https://twitter.com/SeattleParks/status/1329204222634520576