I met this Dutch family in Oban, en route to a cycling holiday in Barra (I was heading to Islay via Colonsay). They had come from near Amsterdam via ferry then trains (and were highly complimentary of both Scotrail and taking bikes on trains in the UK!)
They said the older boy could do 50km a day and there was a special folding hitch on Mum's bike that could turn the younger girl's bike into a tag along. I thought the mini-Ortliebs on their bikes (Raleighs) were quite cute.
And the adults looked to be carrying more weight each than I was!
Anyway, though I would share.