Especially as kids without a mum or dad are 100 times more likely to go off the rails...and when they do, there is no one to care and fight to bring them back to safety, if you know what I mean. Therefore they themselves are more likely to loose their place in the new system/paradise etc, if that is what you believe, so yes it is rather selfish to leave them unguarded and untutored.
The same goes for shunning your DF kids - its completely putting your own place in paradise before being there for them and therefore throwing them to satan, effectively.