Varying an inheritance

I have a client who is entitled to a share in the residue of an estate who, by her own admission, is not very good with money and so to protect her inheritances from being spent unwisely and preserve the money for her future is thinking in terms of varying her inheritance onto a discretionary trust with herself as one of the class of beneficiaries. Although the aim is simply to protect the money from the clients own spendthrift ways, as she is also in receipt of means tested benefits, i am concerned that doing this may be seen as an attempt to defraud the DWP/local authorities (despite that not being the intention).

Does anyone have any thoughts, experience of this or other ideas that may help?