You don't get character growth after assaulting, injuring, kidnapping, and likely murdering people before. You get consequences.
That would make it even worse. Not better, but worse. And if the grandma laughs it off it would show she has zero care for her family and potential consequences. Because her own flightiness, carelessness, and so on just almost got her grandchildren killed.
This is a situation where her grandchildren were about to die, and if things had even gone slightly different would have died. Which is something the author likely won't recognize. As for them the situation was "never going to go that way" and "they had a plot".