I am new to Gramps (and genealogy). I have worked my way around and have successfully built my fathers family tree. He was an only child, so it wasn’t too difficult. I now want to build my mothers family but I cannot find a way to share the people. I was thinking it would be better to create it as a separate family tree?
I would recommend building your mother’s tree in the same database. After all, Your Family Tree will be the combination of both branches. One database also means only one place database to build, one set of sources etc. If you need to generate a report of only one branch, this can easily be done using a filter.
But if you still want two databases with only the shared people brought into the new tree…
Create a filter that selects just the people you want. Then do an export. Select Gramps XML (family tree). In the options set the People filter to the filter you created, make sure no living or private information is excluded, and set the Reference option to Do not include records not linked to a selected person. This last options limits places, events, etc to just those items actually needed by the people and families in your filter.
Once you have the export file, you can create the new database for your mother and then import the file.
Making multiple Trees separately for each spouse would be a mistake that would cause you a great deal of redundant work. Keeping the data harmonized would be confusing. (For instance, you add a Cemetery to one Tree then discover the spouse has ancestors in the same cemetery & have to look up the Address & GPS info again.)
And generally speaking, you’re probably going to find endogamy within a community if the lines have been there for several generations. And pedigree collapse for lines from the same countries.
So you’ll end up putting the 2 trees back together again somewhere down the line.
Just so you are aware, the people in a database do not HAVE to be related. You could have entered all the families on a page of a Census… or the families in a neighborhood. And some of those families may have never intermarried within the community.
But your other question was about sharing the people between branches. Say, for instance, that one of your husband’s 64 sets of 5th great-grandfathers re-married to one of your 5th great-grandaunts. Drag him to the clipboard, add a marriage to the 5th great-grandaunt and drop him into the Relationship/Family as her spouse.
Alternately, you could:
add him using the Select Existing Person dialog. But it is always in Grouped list mode & can be a pain to navigate. Or,
intentionally add a duplicate new 5th great-granduncle with the exact same name (but no Events, Sources, or other stuff so you won’t have to merge those too), sort the Person view in flat list mode, then select & merge the duplicates.