Steve, if you follow the link I provided you will see:-

11. In respect of cash savings the following must be provided:


(a) personal bank statements showing the cash savings have been held in an account in the name of the person or of the person and their partner jointly for at least 6 months prior to the date of application.

(b) A declaration by the account holder(s) of the source(s) of the cash savings.

11A. In respect of cash savings:


(a) The savings may be held in any form of bank/savings account, provided that the account allows the savings to be accessed immediately (with or without a penalty for withdrawing funds without notice). This can include, for those of retirement age, savings held in a pension savings account which can be immediately withdrawn.
(b) Paid out competition winnings or a legacy which has been paid can contribute to cash savings.
The UKBA also state that:-
The cash savings may be held by the applicant, their partner, or both jointly for at least 6 months prior to the application and under their control can count towards the financial requirement where applicable
I am of the opinion that this means the whole amount in your named account, or her named account or a joint account.