The children are playing outside by themselves.
The clouds are opening and a single shaft of divine light is shining down on me! Yes, that is the voices of the angels! The times of, "Boys, go out and play" can begin! Oh sure, someone will get injured after six minutes, but that would have happened anyway. This way I can do some amazing task like, oh, say... clean the kitchen.
These milestones are mixed blessings. Moms always feel some sadness at the little ways in which the baby isn't a baby any more, the small losses of dependence on the mommy...
But wait, let me think.
Nope, I'm completely happy about this.