Thank you for your question.
If you daughter's ex-boyfriend is on the registered legal title to the property and has been made bankrupt then his name will just simply be taken off the mortgage. A creditor may apply to the Court for a charging order over the property. This will then entitle them to apply to the Court for an Order for sale of the property. Your daughter will be able to make representations at those hearings.
The official receiver/trustee in bankruptcy dealing with the boyfriend's case will probably agree to the a postponement of any such application until the end of his first year of bankruptcy in order for alternative housing. Indeed, the creditors may prefer to wait until the property has recovered some equity and there is more to get back. Note though that it is only the boyfriend's share in the equity that is at risk. Your daughter's interest will remain hers, if sold she will receive her share of the proceeds of sale.
She should engage with the official received/trustee in bankruptcy to make sure they are aware of her position. They will listen and she will at least know where she stands with respect to any application to sell the property and will remain informed.
Finally, if your daughter and her ex-boyfriend presently hold their interest jointly (as joint tenants) then each persons share would pass to the other upon death regardless of any director made in the Will. If this is not what you want then you should sever the joint tenancy by using Form SEV from the Land Registry (you will have to send it to them and if you have any questions about completing the form you should call their customer service number - they are very helpful):-
Their interests would then pass according to their wills or under the intestacy rules. The boyfriend need not sign the form provided you follow the instructions.
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