Legal Question in Wills and Trusts in California

You throw a monkey wrench in this question with "(trustee)" but no details or explanation. If any person of any generation directly buys an interest in property for another person, and that person has children at the time or later, and then dies with living children and no spouse, absent testamentary documents to the contrary, the deceased's children would inherit the interest in property. However, if a person buys an interest in property as trustee in trust for another person as beneficiary, unless it is deeded out of the trust directly to the beneficiary, the terms of the trust determine who succeeds to the interest of the beneficiary if they die. Because the details of the trust, and any actions by the trustee after the trust was established, as well as whether there is a living spouse of the deceased are not provided in your question, it is impossible to say who would succeed to the deceased's interest in the property. The only thing I can tell you for sure, is that unless there is a will or trust that says otherwise, if the grandfather is living when the father dies, the sister would definitely not succeed to the interest. In any possible situation where the deceased left no will or trust, the grandfather would be ahead of the sister in the order of intestate succession as long as he outlives the "father."