Protestant work ethic would also absolutely recognise taking care of your family as "work". In fact, it would recognise nearly anything that keeps you non-idle and isn't done purely for pleasure as work. The requirement to be employed in order to receive social help is really weird, it should also factor in any elderly parents and children to take care of. Even from the point of view of complete utilitarianism aiming for maximum workforce, helping parents raise children is a net gain because those children will grow up to be workers, at least until they themselves have children to take care of.