well thats good. When they grow up and if one of them is a conspiracy buff he/she will start to question :)
It doesn't require a conspiracy buff to know that the dates of many Christian holidays are rooted in pagan traditions. That doesn't mean that whatever holy things that day is commemorating are any less important. And besides, these days many do not celebrate them as "holy" but as a cultural day of togetherness, happiness, and shopping!