Gift from out-of-state sister of an off-roster handgun is not allowed, unless it falls into a exemption condition, the only ones of which I am familiar with are
1. intra-familial, which doesn't apply to a sister
2. You are law enforcement and have a legal ok to possess off-roster guns
3. Gun is modified with Single Shot exemption by CA FFL prior to you taking possession.
If I'm wrong about this, another calgunner (or 10) will immediately post corrections. gotta luv this forum.