Hmmm, well one of two things, either you have a crack or that little boy is peeing all over the place. Probably peeing around the toilet seat bolts and it's running down the bolts and dripping onto the flange bolts holes. You basically have to troubleshoot the problem starting with the most obvious and go through a simple process of elimination (no pun intended). You have a few ways in which undiluted urine could drip through the floor close to the seal,
1. No caulking between toilet and floor
2. No bolt caps or no sealing of bolt caps (I put a little silicone on them to make it easier to clean)
3. Crack in toilet
4. Boy peeing in area of bathroom other than IN the toilet, this could be a corner or just straight on the floor.
If all else fails, get a bottle that has a pull up cap like your dishwashing liquid bottle, fill it with water and put a little bit of food coloring in it then start your own tinkle party with the toilet, squirting water here and there and all around and see if you can pin point where it is. Good Luck!