My friend, there's a huge difference between family based green cards (FB categories) and employment based (EB). The wait times change from 1-10 years in the former [1] to 100 in the latter [2]. A normal indian cannot go through family, since they're not closely related to a citizen. I have close relatives who gave birth here (they're working on a H1-B). The mom and dad would make it quicker by waiting for the US citizen kid to become 18 and apply, than they applying.
Heck, they can wait for the kid to turn 18, go to Iceland/Sri Lanka, give birth to the grandkid, and that grandkid can apply for the citizenship and that would be faster. :(
[1] - friends and my roommate here in the bay
[2] - my application
[1] - friends and my roommate here in the bay [2] - my application