Tracking, Wheel alignment, or anything else people commonly call it.

[Pugglt Auld Jock]

It's age Jock, my children are the same, however they still know where to come for help!!!
I have said to them if when they understand what I have told them they simple say, "Oh Dad, I see now , thanks" I would stop at that point however if one is still getting a vacant look, then the explanation will continue.

On the back of our toilet door we have a big notice board where I pin up any amusing father's day cards, it makes a good talking point when friends call. One of my favourites was sent to me by my daughter which shows a younger person sitting on the floor next to a leaking pipe with a bunch of tools in their hands and around them on the floor with the caption "If in doubt, ask DAD!" Pretty much sums up my relationship with my children - Ha ha!