Strongly believe that once npcs come out (mostly like in 5 years lmao) someone will make a mod out of it,
I dont think implementing it in the game itself is very needed, its a bit "useless" or very time consuming.
If we consider realistic time you would need to survive years maintaining your son/daughter until they actually can somewhat defend you and themselves, i can already expect someone saying that the time for a child to grow could be configurable but i still think its a bit of a time consuming addition that in the end might not be very achieved or even used by most players.