How do you know when you reached an inflection point in your life? How can you know that from that moment forward you would be interested in math or enjoy running or pursue a career in gardening? Could you ever tell at the time or is that insight generally reserved with the benefits of hindsight?
Perhaps this is easier for the outside observer. If I were to make a prediction, then I would say that today is the day that my daughter (not quite six years old yet) became interested in playing video games. In the past she generally liked to just watch me play. I would select age-appropriate games and occasionally offer her to take the controller and try it herself, but she would usually shy away. This changed today.
That game today was Seasons After Fall and shortly after starting it, I encouraged her to give it a shot herself. She was unsure at first, but I encouraged her and emphasized that the controls were simple. She went for it! Yes, the Xbox controllers are big for her hands, but she got it this time. Minutes later, the delight on her face was obvious, as the little fox on the screen moved in response to her pressing buttons on the controller.
An hour later she was still at it, getting upset when she ran into trouble, rejoicing when she overcame it. Occasionally she asked me for advice or concrete help for getting past a tricky spot. I would take the controller a few times, but always handed it back after a minute or two.
Witnessing her transformation from observer to reluctant participant to fully engaged player, this sure seemed like a turning point. I could be wrong about it, but just in case, I am noting the prediction here as my best guess.