Because whenever you sponsor somebody, your own immigration history is exposed and reviewed again.
By filing for anybody else, you're going to commit immigration fraud. Any immigration benefit you get your kids may be taken away from them many years later whenever fraud on your part is discovered.
There's more than ever fraud units in USCIS scrutinizing every case. Especially from your country of origin. Especially with prior marriages involved.
I'm not going to go into detail, as you'd just going to think how to defraud US government again.