After gave birth the first child the mom have mission go to mission travel outer space get suck into black hole (Gagantua ),due to the effects of time dilation, a concept from Einstein's theory of relativity. Time slows down significantly for them compared to people on Earth due to the intense gravitational field.
Specifically, during their mission, the mother spends time on a planet where one hour is equivalent to several years on Earth. This extreme time dilation causes her to age much more slowly than her first boy who remains on Earth and experiences time at a normal rate. As a result, by the time mom returns,few decades have passed on Earth, and first boy is now an eldery old man,while mom has only aged by a 10 month.
