您的原話：法律上，夫妻一方死亡，死者孩子應該是沒有繼承權的，隻有配偶繼承，沒有你們希望的三人平分。
現在媽媽和繼父有prenup，不看文字，很難說什麽是community property。
http://www.ca-trusts.com/intestate.html
1. The decedent's community property goes to the surviving spouse, who may have to file a spousal property petition to establish ownership.
2. The decedent's separate property is distributed as follows:
a. The surviving spouse receives all of the separate property if the decedent is not survived by issue, parents, brothers, sisters, or children of a deceased brother or sister.
b. The surviving spouse receives one-half of the separate property if the decedent had only one child, or issue of a deceased child.
c. The surviving spouse receives one-half of the separate property if the decedent left no issue, but left parent(s) or their issue.
d. The surviving spouse receives only one-third of the separate property if the decedent left more than one child.
e. The surviving spouse receives only one-third of the separate property if the decedent left one child and the issue of one or more deceased children.
f. The surviving spouse receives only one-third of the separate property if the decedent left the issue of two or more deceased children.
