Legal Question in Real Estate Law in California

Perhaps, but statements of a non-party to a lease generally will not control its interpretation. You really need to consider whether the lease that you signed is written as a term lease for a fixed number of months (or years), or whether it is clearly month-to-month. Possibly a statement such as the family member made could be argued as a fraud on you, but only if the statement were made before you signed and was intended to induce you to make a mistake as to the wording of the lease,,,,,, all somewhat unlikely. I'm afraid you are stuck with the black and white of the lease itself. However, you can always ask the family member in charge if they'd be willing to let you out of the lease early, and on what terms. You could cite the written statement of the other co-owner in support, to gain sympathy.

You need to comply with the terms of the lease.