I have an account with my family tree but my fiance wants me to start one for his family. Can I have multiple family trees under one account or do i have to set up a new family search account?
Welcome to the "Community.FamilySearch" Forum.
Short Answer: Help/Assist your Fiancé, create, a 'FamilySearch' Account, in his name.
Where, you could can then, help/assist your Fiancé, build, his own "Ancestral" Lines".
And, then, you can join them together, when the time comes.
I hope, that this may help/assist, somewhat.
First of all, let me agree with Brett's suggestion to help your Fiancé create his own FamilySearch account.
However, it will not be his own family tree , anymore than yours is your own.
Family Tree is a global work on a single family tree, with each of us adding our own branches and twigs, discovering other ancestors and branches that we are linked to along the way. It's an absolutely great work to be involved in, but remember, it is a collaborative effort and we need to be understanding of other folk's efforts, particularly when they might seem to conflict with something which we have researched.
Can i suggest as a guideline, that when you or your Fiancé add any names to the tree, you include details about the sources you used to establish the person and their position. Be sure to add notes as well, because this can often help others see why you came to a particular conclusion.
I wish you all the best as you work together in this fascinating project.