Living trust -CA need probate?

my uncle past away a couple of months ago and left a living trust. my mother and brother are the successor trustees. in california if there is a living trust, does it have to go to probate?
also, my uncle's savings account was not included in the living trust. the bank says we need to obtain a letter of testamentary from the court to include that account in the living trust. can i obtain the letter of testamentary from the courts and if so, how would i obtain it?

A living trust does not go through probate, although there are formalities that must be handled, and if there is over $675,000, estate taxes to pay.

As for the bank account that was not registered in the name of the trust, there should have been a "pour-over Will" signed too, that directs that anything not registered in the name of the trust goes into the trust. If there isn't, it goes to the heirs at law, and NOT to the trust.

If the amount is small, there are very simplified procedures in CA for such estates.