What is the husband's share of inheritance if his wife, with whom he had an unoffical marriage (zawaj 'urfi) contract, passes away and they did not have children?

If a woman dies while married to a man, the husband inherits a quarter of her estate if she has a child. The reason for inheritance is the existence of the marital bond. The husband's failure to provide the obligatory maintenance does not affect his right to inheritance, but he incurs sin by doing so, and the wife has the right to refer her case to a judge. However, if the woman agrees to waive some of her rights to maintenance and equitable division for her husband so that he does not divorce her, there is no sin upon them in that, for reconciliation is better than separation.