Good morning. Thank you for the question. It is my pleasure to assist you with this today.
If your father died without leaving a will, then his estate passes under the rules of intestacy which states that a spouse gets the first £250,000 of money and assets and 50% of the remainder and children share the other 50% of the remainder equally.
Whilst I know what your father said on his deathbed and I know what his wife agreed but she will simply deny that in all probability and even if she didn’t, it is highly unlikely to be enforceable without a lot of legal wrangling which is probably going to be more than the amount of money that you are arguing over.
Under the rules of intestacy and taking the house in isolation, there is £20,000 after the spouse allowance of £250,000 of which she would get £10,000 and you and your sister would get £5000 each.
If you could prove that your father promised a large chunk of money to you both and you acted on that promise expecting the money to arrive and you acted to your detriment, you may be able to bring a claim against the estate. It is a legal doctrine called Promissory Estoppel. Because of the circumstances here I think it unlikely you would get a solicitor to deal with this no win no fee although it would be worthwhile making a few telephone calls.
The fact that the house sold for bought than they paid for it is not relevant in all honesty.
Can I answer any points arising from this?