Bubble, that reminds me of my mum.
My nephew was terrified of dogs and by accident mum had agreed to dog sit my cousins golden retriever the same week as nephew (her grandson) was staying for half term.
Fortunately the GR is a very calm and gentle character, but he is very big, and the nephew was at the time quite little.
My mum told my nephew, if you stand still when GR is running round, he will never bump into you. Have you ever seen a dog running round that bumped into a tree? No? Because a dog isn't stupid, they won't bump into something, that would hurt! So pretend to be a tree and he won't bump into you.
All was good, by the end of the week nephew was hugging dog and crying because he had to go home, nephew no longer afried of dogs etc.
So I used that with my kids - pretend to be a tree, dogs never bump into trees do they? Worked fine until the friendly slightly over weight lab that was out for a walk with us crashed into dd and bowled her over. She got up rather crossly and said Well, I obviously wasn't a good enough tree!