Legal Question in Real Estate Law in California

Yes, but you should make sure everything is set up to make that happen, now. You don't mention who the trustee is, or who the successor trustee will be when your mom passes (assuming she is the current trustee). If everything is set up right, the property doesn't transfer at all; there is just a requirement to file a notice of death of trustee and successor trustee. It is a tax neutral event. If the house stays in the trust until sold, there is never any reassessment event. If title is distributed out of the trust to one or both beneficiaries, you should have a trust attorney guide you through that to make sure it is not reassessed.