How to properly work with tenant to consider other options

[Louis Ramos]

I have an owner who is currently renting a 650 sqft studio a mother with 2 teens. The owner was doing more of a favor to get her back on her feet. But she recently had another child so there are now too many people living in the unit. This property is in Los Angeles. Is not RSO. The tenant has also not been the best tenant. What is the best way the owner can properly approach the tenant to consider other options/evict due to the small space.