Also...your post's title was so long it got truncated to:
"Travelling with adult children mid 30s to 40, 6 to ".

...6 to WHAT?!?? You never did explain that mystery... Was that perhaps the beginning of a reference to the number of adult children? Was that a reference perhaps to the number of grandchildren they are bringing along?Was that the begining of a reference to the ages of said grandchildren?

Without that information your post reads like you don't trust your 30-40 year old children to be on their own...hence the confusion and perplexed responses you are getting...
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