What is the ruling on a young son being alone with his young mother if he is negligent in fulfilling God's rights and often stays out late?

Originally, it is permissible for a son to be alone with his mother and to look at what is ordinarily visible of her body, because she is one of his mahram. However, if fitna (temptation/strife) is feared, and signs of suspicion appear from the son, then it is obligatory to block the means (sadd adh-dhara'i') that lead to the unlawful. In such a case, the mother must avoid being alone with him or not wearing a hijab in a way that leads him to look at her with desire. Scholars have unanimously agreed on the prohibition of looking at a non-mahram woman and female mahram relatives with desire.