In California, person dies intestate, heir assigns his interest but dies, is the assignment valid?

A woman dies intestate with no spouse (divorced), no children, predeceased parents. Upon her death she had four siblings all living (none predeceased). During probate, one sibling assigns his interest in the estate to another sibling, but before everything is finalized, he dies. He has three children. Without the assignment, the three children would divide his share. Does the assignment hold, even though he is no longer a "surviving" sibling when the estate is distributed? In other words, will the sibling receive his share, or will his children?