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Hi Mr Veritas, yes as with MarkRae - only seconds, done in fun, held securely, as a game, held still, not swung around or anything, just a second then up again. Not sure what child thinks - looks unsure.
Dad is bit hyper sort of person, does things on spur of moment, he is just playing and thinks his son is fine.
All yr answers have made me feel a bit better about it - although I still certainly wouldnt do it myself - and wouldnt want anyone else doing this to my kids.