Friend, it's really not a matter of "getting" younger people. It's a matter of safety for your cousin. (Bear in mind that less than ten years separate us in age xD) It would be different if your cousin knew something about horses, and you were just giving her some suggestions about something specific, like posting or picking up the correct lead.
But, based on what you've been saying, it just kind of sounds like the blind leading the blind. Plus, you've given some contradictory statements here about your knowledge, and about what you'd do in a given situation, which makes your experience level difficult to gauge, or hard to believe.
The sensitivity of the internet baffles me.