Iceland with a 5 yr old child as a pillion?

[Wheelie]

My original plan was to ride alone, from Reykjavik and then through the interior and then round west, alternatively a different route back through the interior. Trip duration estimated to one week. Bike is a BMW F650GS Dakar

Lately though I have been contemplating taking my five year old son as a pillion. He will be close to six when it is time to go late July or early august. At the moment he is 118cm tall. I have not checked to see if he can reach the foot pegs this year, but I have both a child harness to strap him to me and a child seat as an alternative.

What do you guys and gals think?

I am not too much concerned with gravel, rock and ruts or river crossings - I would just have to be very careful.

My greatest concern is riding in sand with my child and a heavy loaded bike (BMF F650GS Dakar). If it is only a few kilometers, then I could always walk him across bit by bit, backtracking to ride the bike bit by bit, a few hundred meters at a time. But if it is more than a few kilometers, then it might just be too much. Any of you know how much sand I should expect? The longest continuous stretch?

My second greatest concern is if he is just too young to appreciate it... hours in the saddle, little playtime, no electronic entertainment, few toys, no interaction with other kids, camping, eating poorly, no showers, cold, wind, rain, no toilets, etc... I really want to share my overlanding passion with him but don't want to squash his interest by setting off before he is of age.

Any comments will be appreciated.