Virtually all Wills drawn up by a lawyer include a standard 30-day Survivor Clause meaning if the spouse does not survive for 30 days, then the secondary designated beneficiaries kicks in, in this case the four children. The reason for that is there can be various circumstances such as a plane crash or car accident when it becomes impossible to determine who died first, and so it minimizes needless estate fees. We don’t know if Barry’s Will included such a clause but I’d be very surprised if it didn’t given the magnitude of his estate.
What we don't know is whether the killer or the person who arranged these murders 1) had any knowledge about 30 day Survivor Clauses, or even how succession rules would apply in the case of them both dying on the same day; and 2) had any knowledge about the actual contents of Barry's Will. They may have just assumed that if BS died first, BS Will would leave everything to HS.
I think HS may have told certain people that she was leaving them substantial amounts of $. They may have assumed or understood or even been told that that this was set out in her Will. There are already reports that HS "promised" MS hundreds of millions of dollars. Conversely, there may also have been a fear amongst certain people that thought that they should be potential beneficiaries of HS that HS would leave all her wealth to charities (or other people and not them) once she passed away.
IMO if one assumes they were murdered for money, one possible scenario could be as follows: (there are others):
Someone believed they should be beneficiaries of HS, but either had been told or assumed that they would be left nothing by HS. They assumed that BS' Will bequeathed everything to HS if BS passed way first; and that if HS predeceased BS that BS Will left them an inheritance. Most importantly, they wanted or needed the money now.
Under this scenario, if HS died a year or 2 after BS died they would receive nothing, as all BS' money would have gone to HS and they werent a beneficiary of HS. If HS passed away a few years before BS they would have to wait until BS passed away in order inherit; and there was a risk that in the interim BS could have altered his Will to reduce or eliminate their inheritance. The only way for them to guarantee themselves receiving an inheritance, and receiving it now would be if BS and HS were to pass away together, thereby invoking the 30 day clause.
MOO -- not trying to accuse anyone of anything here, just pointing out a possible scenario