Settlor death during purchase

I have a situation where a mother is buying a property for her ‘vulnerable’ son which is to be held in trust for him when she goes into a care home. Unfortunately it looks as if she may not survive until completion. I have just found out that the funds are being held in an account in her daughter’s name. How do I provide for this situation in the will? She has rallied and it may be that she will survive long enough for us to complete but it is not certain. I am very worried about this situation and would appreciate any words of wisdom.

I assume that you were awaiting completion before drafting a will [or lifetime settlement] in anticipation that this would make the subject matter of the trust easier to describe? If so, should you not be preparing a will asap [subject to capacity concerns, of course] describing the initial trust assets as best you can; eg “all the residue” or “the sum of £X”?
Or are you more concerned about the funds in the daughter’s name? Might she be acting as an informal “trustee” intending to carry out Mum’s wishes; but who would inherit as matters stand, and what complications would/could this lead to?

Hi Kevin. This was presented to me at a late stage so I couldn’t do anything before now. The funds do concern me but believe they will be used for designated purpose and declared. It’s more how I draft the clause in the will to enable the purchase to complete ( needing to ring fence funds) bearing in mind that she may live long enough and no provision would then be needed in the will. Thanks so much for replying.