Abu Dawood: Hadith 2261

Abu Hurairah said A man from Banu Fazarah came to the Prophet (ﷺ) and said "My wife has given birth to a black son" . He said "Have you any camels?" He said "They are red" . He asked "Is there a dusky one among them?" He replied "Some of them are dusky" . He asked "How do you think they have come about?" He replied "This may be a strain to which they reverted" . He said "And this is perhaps a strain to which the child has reverted."