I don't have kids, but I have told white lies to them in occasion.
Once when I was on teaching prac, there was a bank robbery at the nearby shopping centre and the robber got away. We had an announcement over the PA to bring the kids inside, lock the doors and keep them away from the windows. When the lockdown was over we were told by a teachers aide what happened, but we didn't share this with the children as we didn't want to excite them too much before the end of the day. So I just told them I didn't know what was going on.
But, some of the children came back from special reading group and they had been told what had happened and shared it with everyone else.
And it did excite e kids, got them fostered from cleaning up after a craft activity. I continually had to tell them not to stand around the door gossiping.