Wherever in the world you live - different countries, different continents - few experiences can instantly unite two seven-year-olds better than the chance to peer down a medieval castle toilet.
When I was young, the craze at school was for having a penpal abroad. You would fill in your details on tiny little forms, and within weeks you'd have received a letter from a strange foreign child with whom you had absolutely nothing in common.
All the ridiculously high hopes I had as a child, filling in those forms, have been answered so many years later by blogging. This week we met the Speechless family for an unbelievably lovely day touring a castle and walking in the sunshine. The adults talked about everything under the sun; the children threw stones in a stream, got their feet wet, played with gravel and brandished sticks.
Tess was right. That my blogging friendships can also give my children such joy is incredibly precious. No filling in forms for Littlest - no letters from strangers. She's from the Skype generation. She's planning video clips, online conversations. The world is getting smaller, and I'm all for it.