Age of overnight carer

We’ve a situation where a 13 year old grandchild sleeps overnight to be on call for disabled grandparent.  Is she too young to be considered an “overnight carer”?  The legislation just says “one or more people” and I can’t see any case law on it.  And if 13 is too young, what about 16?

Is the local authority aware that the child is caring for the grandparent? I don’t see it being a real problem I assume this is for HB, but see “Young carers” section below.

https://www.carersuk.org/help-and-advice/practical-support/getting-care-and-support/young-carers-and-carers-of-children-under-18

thanks I will pass this on to colleague