Thanks! I just checked CA regulations and found the following:
The transfer of a firearm between a parent and child or a grandparent and grandchild is exempt from the dealer transfer requirement. The exemption does not apply to step-children/step-parents, brothers, sisters, aunts, uncles, or cousins.
If the firearm is a handgun, the recipient must obtain a Handgun Safety Certificate prior to taking possession and must also submit a Report of Operation of Law or Intra-Familial Handgun Transaction and $19 fee to the DOJ within 30 days after taking possession.