All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
First of all, we advise both spouses to have a mutual understanding in regard to any matter over which they may disagree or differ, and each one should respect the other and know his/her status. Each one of them was gracious towards the other (during their marriage). Allah says (what means): {And do not forget graciousness between you.} [Quran 2:237]
It is detestable for the husband to describe his wife as a devil; this is contrary to the teachings of the Quran, as Allah says (what means): {And live with them in kindness.} [Quran 4:19]
So one should block any door which would enable the devil to use in order to create disputes, and which may even result in separation. Allah says (what means): {And tell My servants to say that which is best. Indeed, Satan induces [dissension] among them. Indeed Satan is ever, to mankind, a clear enemy.} [Quran 17:53] This instruction becomes more confirmed among the spouses.
There is no doubt that the evil eye is true (a reality) as proven in the Sunnah. The most important thing through which one can repel an evil eye is by protecting the children (by reciting Quran Ruqyah on them), and by teaching those who reach an age of distinction and are able to ration amongst them how to protect themselves.
Ibn ‘Abbaas narrated that the Prophet used to seek refuge in Allah for Al-Hassan and Al-Hussein (and protect them by) saying: "I seek refuge for both of you in Allah’s perfect words from every devil and every poisonous thing. He would then say: 'Prophet Ibraaheem used to seek refuge in Allah for Is-haq and Ismaa’eel, may Allaah exalt their mention.'" [Abu Daawood and At-Tirmithi]
They were both beautiful children, especially Al-Hassan who resembled the Prophet but the latter did not prevent him from mixing with people.
Hence, you should not be very strict on this matter and make it a cause of differences amongst you. Rather, it is more appropriate to protect your children by utilizing means of protection from evil eye, especially that the relatives are generally compassionate and keen on warding off harm from the children of the family. However, if it is possible to conceal some of their beautiful features, then it is good.
Ibn Al-Qayyim said in his book Zaad Al-Ma’aad concerning the treatment of the effect of an evil eye: "Among the treatment from the evil eye is to conceal the beautiful features of the person who is feared to be affected by the evil eye with something that would ward it off; Al-Baghawi said in his book Sharh As-Sunnah that ʻUthmaan saw a handsome boy and said, 'Blacken the dimple in his chin lest an evil eye affects him.'" [End of quote]
Allah knows best.