Is it obligatory to speak with one's mother, brothers, and sisters and to interact with them, or is it sufficient to obey them and offer them help when needed or ill? And is a person excused in this regard if this is their nature?

Filial piety towards parents is one of the greatest duties, and piety towards the mother is more emphasized than piety towards the father. You must be dutiful to your mother and obey her in what is right, and converse with her and befriend her if she is pained by lack of conversation, as long as no harm comes to you. Your conversing with your mother, if it comforts her and brings her joy, is required. So, be keen on everything that pleases her, as this is part of complete filial piety and benevolence. As for your siblings and other relatives, you are not obligated to converse with them at length; what suffices to remove estrangement and abandonment is enough. Maintaining kinship ties has degrees, some higher than others, and whoever wishes to ascend should endear themselves through as much good as they are able. Good manners are acquired through habituation and practice, and there is no accountability for what is beyond a person's capability.