While saying a family Rosary the other night, we were telling our children about the Trinity. We said that God was one god in three persons. Without any further explanation, our five-year old son started to think about this and then said, "Jesus is his own father? That's crazy!"
A few days ago I was at Eucharistic adoration with my daughter and son. The Blessed Sacrament was exposed in front of us, but my son wanted to go back to the tabernacle as we usually do. I tried to explain to him that Jesus was right in front of us in the monstrance, so we did not need to go to the tabernacle, although he was in both places. He found that concept confusing.
Leave it to children to lead us to the core of Mystery, and to remind us that while there is much God has revealed to us and much that reason can make out, in the end God cannot be comprehended by our limited minds, no matter how much we may think we have the idea of of God under control.