Maybe it is due to Hereditary Factors

Abu Hurayrah its narrated, "A man came to the Prophet and said, 'My wife gave birth to a black child.' The Prophet asked him, 'Do you have camels?' The man replied, "Yes." The Messenger of Allâh asked him, 'What color are they?' The man replied, 'Red.' The Messenger of Allah then asked him, 'Is there a grey one among them?' The man answered, "Yes." The Messenger of Allah then asked him, 'Where has that grey) one come from?' The man said, 'Maybe it is due to hereditary factors.' The Prophet , "Maybe your latest son has this (black) color due to hereditary factors
Reported by al-Bukhari, "Book of Divorce," hadith no. 5305. It was also reported by Muslim, Imam Ahmad, Ibn Majah and an-Nasa'i.

Explanation of the Hadîth

This hadîth sets an unprecedented basic rule in genetics, as the hereditary factor mentioned here refers to early generations.
The fact that the offspring bears hereditary traits from both of his parents, who share in giving him these characteristics in various proportions, is something that has been known a long time ago.

But the fact that this genetic line could stretch up to his early ancestors, had only been discovered after the basic principles of genetic inheritance had been uncovered at the end of the 19th century (1865-1869) by Mendel the Austrian monk. Experimenting with breeding garden peas, Mendel grew hybrid offspring that resembled one parent rather than a blend of both parents.
He conceived of hereditary units, now called genes that expressed dominant or recessive characteristics. Until the beginning of the 20th century, "Genes" remained as mere symbols used to explain the variation in creation, until Thomas Morgan (1866-1945) who discovered how genes are transmitted through the action of chromosomes, confirming the laws of heredity of Austrian botanist Gregor Mendel' and laying the foundation for modern experimental genetics. The experiments he and his students conducted with vinegar flies proved that chromosomes behave similarly to Mendel's description. Morgan and his co-workers also created linear chromosome maps in which genes are assigned to specific positions.

'see Mendel's Laws. In 1955, James Warson and Francis Crick each helped determine the structure of the nucleic acid known as deoxyribonucleic acid (DNA), which transmits genetic chorontariotice from ano nonoration to the novt Thor, nlan discovered its ability to divide, and replicate into two identical strands before each cell division. If we trace this replication process back in time, the same old genetic code will end up in billions of people who are on earth today, to billions who died and billions who will come after us.

All of this goes back to one genetic code that was in the back of our father Adam EEN when he was first created. The variation in the characteristics of this code through inheritance is what gave humanity all this variation in its physiological, behavioral and psychological traits.

Thus, all the individual traits, inclinations, taste, moods, color, length, blood type, etc. are inherited from his/her ancestors on his/her father's and mother's sides. Some of these traits are dominant and some are recessive, but some of these recessive qualities may appear in one of the following generations. This shows clearly the great sign in the hadîth of the Prophet *, "Maybe it is due to hereditary factors."

For sure, this is a scientific fact that had only been discovered in the early years of the 20th century, and had been concluded only towards its end. But the Prophet die mentioned this scientific fact very clearly and with great confidence as he derived it from the Divine Revelation. Peace and Blessings of Allâh be upon the last of His Prophets and Messengers, Muhammad .