Responses

And the seller actually asked if he planned to take care of the parents as well...
Why would you take care of those who abandoned you? No matter the reason they gave up parental rights and lost all rights to be parents in the future. Any children coming after would be very wary to be sold and likely have no qualms betraying parents who are more a threat than aligned with their interests and wellbeing.
Fuck the parents they were selling their daughter