Hi.
Any particular reason for doing so?
As far as I know you may not as the kids cards normally can't be used for certain things are restricted for security of the child.
With my starling kid card. I just add him £20 on the card to use so he can tap and pay from the physical card.
If they are over 16 you can just order them a normal Starling card and then they can keep the minimum in their main account and rest can be moved to a space for security.
I hope this helps.
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