My late father left a plot of land by will to our young child. My ex-husband wants to sell it. Can he do that?

Not as he pleases; the law limits a guardian's power to sell land owned by a minor. The father is the primary guardian of his child's person and property until the child turns eighteen, even when custody is with the mother. But a guardian may sell the child's land only in certain cases, for example when the child has no other means of maintenance, or when the price offered is at least double its value. If the will itself says the father may not manage the property, the court will appoint another guardian. If you are worried, the Syariah court can bar the father from selling, charging or leasing the land without the court's permission. Keep copies of the will and the title, and ask the Syariah court about the application procedure. See custody and lineage.