My name is***** and I will be helping you with your question today. This is for informational purposes only and does not establish an attorney client relationship.
If I have this correct, your father died in 1967, His mother (your grandmother in question) died in 2010 and your step grandfather also died in 2010 after your grandmother.
See below for Florida intestate
NRS 134.010 Vesting upon death of spouse; applicability of chapter only to separate property. If a decedent leaves a surviving spouse:
(1)Community property with right of survivorship
vests in accordance with the right of survivorship;
(2)All other community property vests as provided in NRS 123.250; and
(3)The provisions of this chapter apply only to the separate property of the decedent.
NRS 123.250 Ownership of survivor upon death of spouse; disposal by will of decedent.
(1) Except as otherwise provided in subsection 2, upon the death of either husband or wife:
(a) An undivided one-half interest in the community property is the property of the surviving spouse and his or her sole separate property.
(b) The remaining interest:
(1) Is subject to the testamentary disposition of the decedent or, in the absence of such a testamentary disposition, goes to the surviving spouse; and
(2) Is the only portion subject to administration under the provisions of title 12 of NRS.
NRS 134.030 Descent and distribution.
If a decedent dies intestate and has title to any estate
which is the separate property of the decedent and which is not otherwise limited by contract, the estate descends and must be distributed, subject to the payment of the debts of the decedent, in the manner provided in NRS 134.040 to 134.120, inclusive.
NRS 134.040 Surviving spouse and issue.
1. If the decedent leaves a surviving spouse and only one child, or the lawful issue of one child, the estate goes one-half to the surviving spouse and one-half to the child or the issue of the child.
2. If the decedent leaves a surviving spouse and more than one child living, or a child and the lawful issue of one or more deceased children, the estate goes one-third to the surviving spouse and the remainder in equal shares to the children and the lawful issue of any deceased child by right of representation.
NRS 134.090 No surviving spouse but issue. If the decedent leaves no surviving spouse, but there is a child or children, the estate, if there is only one child, all goes to that child. If there is more than one child, the estate goes to all the children of the decedent, to share and share alike.
If the grandparents both died without wills, then they passed away intestate. When your grandmother passed away, 1/2 of separate property went to the step grandfather and 1/2 of the separate property would go to the issue (your dad) or his issue (you). 100% of the community property would go to your step grandfather. Since your dad was dead (I'm assuming there were no other siblings as they would have rights under intestate succession) you would inherit his share (I'm also assuming you have no siblings as they would have rights as well). Upon your step-grandfather's passing, his estate would flow downward through his issue (his daughter) who would receive his entire estate. So you should receive half of your grandmother's estate of separate property(if all of my assumptions are true) but receive non of your step grandfather's estate as it would all go to his daughter. The separate property would be an issue but passed as I stated previously.
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