The Onedin Line (1971) : 7x2

Leaving Letty feeling adrift in their new, large country house James sails to Belfast, persuading cash-strapped Captain Seth Burgess to cut him into his steamship line. William returns from two years abroad and instantly detects the cool atmosphere between his parents. Samuel and Charlotte make it clear to him that they want nothing to do with him but feel remorseful after William dies, saving a group of children from being trampled by a runaway horse and cart. His death also goes some way to reconciling his parents.