Its' not a "Trojan horse" if there are kids involved, just resentment from the first family that the dad didn't die sooner, and leave it all to them.

I know of a case like that, and all I see is a bunch of middle-aged offspring resentful of their widowed dad's happiness after he remarried and started a new family.

"How dare he! We had plans for all the money we were going to inherit!"