Apparently reincarnation is the philosophical and religious concept that a living being starts a new life in a different body after each death.
The idea of reincarnation is found in many ancient cultures, and a belief in rebirth that was held by such historic figures as Pythagorus, Plato and Socrates.
The word 'Reincarnation' derives from Latin (Lucifer's language), literally meaning, "entering the flesh again".
The above obviously is hugely incorrect as reincarnation never existed.
The current population is 7.4 billion (17/07/2016). http://www.worldometers.info/world-population/
Mary when on earth only had one son Jesus. She would had more, but she knew that one child was the limit. The maximum children to any couple should be one.