both dh and I often go away for work.
That means I have left them dozens of times, for a few days each time. But they are left with their dad, and vice verse.
We once were both away (work) at the same time, and a good friend came and house/kid sat for us for 5 days (kids were teens)
As for both of us away for a holiday together and leaving kids, hardly ever.
One weekend on our 10 wedding anniversary.
One weekend 2 years ago.
Maybe once or twice other than that? But really hardly at all.
They have left us plenty of times for camps and going away with friends etc.
But we can never seem to get them to all go away at the same time....