If somebody dies intestate (without a will) leaving both a spouse or civil partner and children, the spouse or civil partner is entitled under law to receive specified personal possessions plus a fixed sum. On 26 July this sum (known as the statutory legacy) was increased from £270k to £322k. If the deceased's net estate exceeds this amount then the balance of their assets will be divided so that the spouse receives half and the children will receive the other half equally between them.
This can lead to difficulties (for example, a parent or step-parent owning a house jointly with their children or step-children) and many married people may prefer their spouse to inherit everything. It is always preferable to make a will and take control of who will benefit from your estate.
The change to the fixed sum also highlights the fact that unmarried partners have no entitlement under intestacy law even if they were cohabiting with the deceased. They may be able to bring a claim against the estate but this can be a lengthy, stressful and expensive process and there is no guarantee of success. It is always better to make a will to protect your loved ones and not leave it to the law to decide who will inherit your assets.