Well I can understand that they might worry about your driving (although why should they?) But having to ask if you can take him out for a walk just seems weird. Are they expecting werewolves? When I looked after GS1 from the age of 6 months we just went wherever and did whatever we fancied. It never occurred to me - or DD that we wouldn't. I wasn't as involved with GS2 & 3 but there was never a problem with what I did with them.
Lest we forget what we have just lost ....
This would under normal circumstances be headline news
maybe they solved the childcare issue but a much bigger and more important issue needs to be resolved; the relationship between the family members.
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. It's extremely unlikely that they'll find a childminder who'd be prepared to look after their child under such restrictive conditions.