My question is about mahram and na-mahram. Some people, i.e. sons and daughters of uncles, who share the same house like brothers and sisters do, keep on behaving carelessly near each other. Although it is known that they are legally possible to marry, they do not wear scarf and do not behave like na-mahram to them. Does the term 'growing up like brother and sister' exist in Islam? Are there any verses or hadiths about this?
The persons near whom Muslim women can uncover their heads is revealed in the following verse:
“Tell the believing women to reduce some of their looks, and cover their private parts. Tell them not to uncover their beautiful parts except what is naturally seen. Tell them to put their headscarves onto their chests and not expose their beautiful parts except to their husbands, their fathers, their husbands’ fathers, their sons, their husbands’ sons, their brothers, their brothers’ sons, their sisters’ sons, their women, those in their possession, those male attendants that have no sexual desire to women, or children who are not yet aware of the private aspects of women. And tell them not to stamp their feet on the ground for their beautiful parts to be noticed. Believers! Return all together towards Allah, so that you may attain what you hope for.” (The Light 24:31)
The expression ‘grown up like brothers and sisters’ does not comply with Islam. It is a term made up later on. The Glorified Allah sets this ruling, although He informs in Quran that all the people are brothers/sisters. Our Prophet had grown Ali at his own home but then had him marry his daughter Fatima. Growing up like brothers and sisters is not possible for the children of uncles, who are not obstructed from marrying. Everybody must care about these points.