Since your husband has passed away, then if his mother did not leave a will, her home and any other assets she may have will most likely end up in probate court and the court will determine the distribution of the assets.
Normally the first people to be considered by the court as heirs would be the spouse (if there was one) or any other living children that she may have. However, anyone can file a claim with the probate court to be considered in the distribution of the assets. Since your husband's name was on the land registry, then the court may consider your claim, but it will really depend on what other living relatives the mother may have, such as other children or grandchildren, etc. But you are certainly entitled to enter your claim, and you would be considered by the court in the distribution of her assets.
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