Since the consumer already has title to the property, the purpose does not appear to be “purchase”. It appears that the proceeds of the loan will be used to pay the mother’s existing debt. This scenario appears consistent with a “refinance,” except that the old debt and the new debt don’t involve the same consumer. By default the purpose should be “home equity.”
You appear to have a changed circumstance, so a revised LE is appropriate. Both the revised LE and the CD should indicate the purpose is “home equity.”
Since the new loan is secured by property the consumer already owns, the transaction is subject to the right of rescission if the house is the consumer’s principal dwelling.