You must shake your boyfriend out of his delusion that a will is a suicide note. It is causing grief already, may cause far more when he dies and will also cost more to sort out than if he writes a will.

Tenancy in common is where you each own separate shares of the property, with which legally you can do as you please. However, it makes sense only if you write a will in favour of the person you want to inherit your share. Otherwise, it will pass according to intestacy laws.

Martyn Gowar of the Chartered Institute of Taxation said: “Common-law spouses do not have automatic rights. Under the Administration of Estates Act 1925, if your partner died without leaving a will, spouse or children, his estate would go to his mother.

“When she dies that 25% share in the property would be distributed according to her will, or if she has no will according to the intestacy rules, which means it is then likely to go to your partner’s sibling.”

Last week’s Law Commission report could solve your problem, as it recommends that people who have lived together for at least five years should have equal rights to those of a spouse. But that is only a consultation, which might not become law for years. You cannot wait that long.

You do not say how well you get on with your boyfriend’s family but I would not be keen to see a 25% share in my home bouncing around like an out-of-control balloon.

They could theoretically sell that share, make it difficult for you to move home or quibble over repairs. And they may not be able to keep up the mortgage payments.

Assuming your boyfriend has drawn up his life policy properly, you will receive the proceeds when he dies without it touching his estate.

Bob Fraser, senior wealth adviser at Towry Law, said: “If you paid off the mortgage, you would simply have paid the debt on his estate. The 25% share of the house would remain in the hands of his mother. You could use the proceeds of the life policy to buy the 25% share from his mother, leaving her to use that money to settle the mortgage. She would benefit to the extent to which the proceeds exceeded the balance of the mortgage.”

If the property was held as joint tenants, which is possible even with a 75:25 split, your boyfriend’s share would go direct to you on his death. But if you die first your 75% goes to him, irrespective of what your will may say.

It sounds as if you and your partner dived into the house purchase without thinking through the implications. If, as you imply, your share in the home is debt-free, you and your children have the most to lose — not least from inheritance tax. Don’t let silly phobias get in the way. Straight thinking now will save a great deal of pain later.