It is not true. There is no law which states that a father cannot live with his daughter.
Frank W. Chen has been licensed to practice law in California since 1988. The information presented here is general in nature and is not intended, nor should be construed, as legal advice for a particular case. This Avvo.com posting does not create any attorney-client relationship with the author. For specific advice about your particular situation, please consult with your own attorney.
Your landlord is full of it. This is housing discrimination. File a complaint with the Department of Fair Employment and Housing (DFEH) at: http://www.dfeh.ca.gov/
Most likely, DFEH will not act because they are overwhelmed with issues and understaffed; but at the very least, they can supply you with information and that can put your landlord in her place.