Russia went for most of the 1700s with the list of those in Line for Succession being *extremely* short. (It makes Britain in the early 1800s look in great shape)
From Peter the Great (died in 1725) who only had two children live to adulthood (Anna and Elizabeth) through Paul who became Czar in 1794 with two sons and 4 daughters, (and who his mother may have wanted to skip over), the line of succession was short antagonistic and ugly among those few in it. It seems that the idea of completely running out of Czars in the Romanov line is not too odd? It would seem that the most likely scenario would be Elizabeth dying in the first year of her rule, before she set her nephew Peter (OTL PeterIII) has her heir. The infant Ivan VI would have to be killed of course, but given that Elizabeth had him imprisoned, that shouldn't be too tough.
If this happens before July 1741 then I believe that the only living descendant of Peter the Great is Ivan VI's mother Grand Duchess Anna Leopoldovna who is pregnant (with a daughter) and imprisoned with Ivan VI...
From Peter the Great (died in 1725) who only had two children live to adulthood (Anna and Elizabeth) through Paul who became Czar in 1794 with two sons and 4 daughters, (and who his mother may have wanted to skip over), the line of succession was short antagonistic and ugly among those few in it. It seems that the idea of completely running out of Czars in the Romanov line is not too odd? It would seem that the most likely scenario would be Elizabeth dying in the first year of her rule, before she set her nephew Peter (OTL PeterIII) has her heir. The infant Ivan VI would have to be killed of course, but given that Elizabeth had him imprisoned, that shouldn't be too tough.
If this happens before July 1741 then I believe that the only living descendant of Peter the Great is Ivan VI's mother Grand Duchess Anna Leopoldovna who is pregnant (with a daughter) and imprisoned with Ivan VI...