Born on May 30, 1672, Peter was named Peter Alexowitz, meaning 'Peter the son of Alexis'. His father, Tsar Alexis, had married twice, and Peter was the first child
of his second marriage. There were already six daughters and two rather unhealthy
sons, named Feodor and Ivan, from the first marriage. When Alexis died very
suddenly ia 1676, Feodor ruled until his own death in 1682, when the ten year old
Peter became tsar jointly with his half-brother Ivan. It was not until 1696 that Peter
began to rule alone.

Why did Peter not immediately become Tsar when his father died?