Sa'id bin al-Musayyib narrates from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that a Bedouin from Banu Fazarah came to the Prophet (peace and blessings be upon him) and said: My wife has given birth to a black child. He (peace and blessings be upon him) asked: "Do you have camels?" He said: Yes. He (peace and blessings be upon him) asked: "What is their colour?" He said: Red. He (peace and blessings be upon him) asked: "Are there any ash-grey camels among them?" He said: There is an ash-grey camel among them too. He (peace and blessings be upon him) asked: "Where did that come from?" He said: Perhaps because of some strain (in their lineage). The Prophet (peace and blessings be upon him) said: "This too may be because of some strain."
(b) In the narration of Qutaybah: A man from Banu Fazarah came to the Prophet (peace and blessings be upon him), and he (peace and blessings be upon him) said: "It may be that some strain drew it out."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب اللعان / 15363