Did the parents of the Prophet (peace and blessings of Allaah be upon him) become Muslim?
Question

Did the Prophet's() Grandfather, Father and Mother ever believed in Allah? All the Prohets before the Last Prophet(), were their religion called Islam?.
Praise be to Allah.Discussion of the grandfather of the Messenger of Allah (peace and blessings of Allah be upon him) comes under the heading of rulings on the people of the fatrah which, as Ibn Katheer said, refers to the interval between two Prophets, such as that between ‘Eesa (peace be upon him) and Muhammad (peace and blessings of Allah be upon him), when there was a break in the Message.
(Tafseer al-Qur’aan il-‘Azeem, 2/35. See also Jam’ al-Jawaami’ by al-Subki, 1/63; Rooh al-Ma’aani by al-Aaloosi, 6/103. 
The scholars divided these people into two categories: 
1 – Those whom the call reached and
2 – Those whom the call did not reach, so they remained unaware. 
The first category may be further divided into two groups:  
(i)Those whom the call reached and who believed in Allah alone and did not associate anything with Him, such as Qiss ibn Saa’idah and Zayd ibn ‘Amr ibn Nufayl. See al-Bidaayah a’l-Nihaayah, 2/230; Fath al-Baari, 7/147.
(ii)Those whom the call reached but they changed it and associated others with Allah, such as ‘Amr ibn Luhayy who changed the religion of Ibraaheem and of whom the Prophet (peace and blessings of Allah be upon him) said: “I saw ‘Amr ibn ‘Aamir ibn Luhayy al-Khuzaa’i dragging his intestines in Hell.” Narrated by al-Bukhaari, 3521; Muslim, 2856.
It was narrated from the Prophet (peace and blessings of Allah be upon him) that his parents are in Hell. Muslim (203) narrated that a man said: “O Messenger of Allah, where is my father?’ He said: “In Hell.” When the man turned away, he called him back and said: “My father and your father are in Hell.” 
With regard to his mother he (peace and blessings of Allah be upon him) said: “I asked my Lord for permission to pray for forgiveness for my mother, and He did not give me permission. I asked him for permission to visit her grave, and He gave me permission.” Narrated by Muslim, 976. 
Al-Nawawi (may Allah have mercy on him) said, commenting on the first hadeeth: 
This indicates that whoever died during the fatrah (interval between two Prophets) following the way of the Arabs at that time, namely idol-worship, is among the people of Hell. We cannot say that the message did not reach these people, because the message of Ibraaheem and other Prophets had reached these people. 
Sharh Saheeh Muslim, 3/79. 
However some scholars have tried to defend the parents of the Prophet (peace and blessings of Allah be upon him) and say that they will be saved from Hell, and that Allah brought them back to life after they had died, and they became Muslim and believed in the Prophet (peace and blessings of Allah be upon him), then they died like that (as Muslims). They quoted as evidence for this mawdoo’ (fabricated) and da’eef jiddan (very weak) ahaadeeth which cannot be regarded as evidence. 
See al-Haawi li’l-Fataawi, 2/202 
The scholars refuted this idea. 
Al-‘Azeemabaadi said: 
Everything that has been narrated concerning the parents of the Prophet (peace and blessings of Allah be upon him) being brought back to life and believing and being saved is mostly fabrications and lies, and some of it is da’eef jiddan (very weak) and is not saheeh at all, according to the consensus of the leading hadeeth scholars who judged it to be mawdoo’ (fabricated) and da’eef (weak), such as al-Daaraqutni, al-Jawzaqaani, Ibn Shaheen, al-Khateeb, Ibn ‘Asaakir, Ibn Naasir, Ibn al-Jawzi, al-Suhayli, al-Qurtubi and others. ‘Awn al-Ma’bood, 12/494. See also Majmoo’ al-Fataawa, 4/324 
We should understand that blood ties will not save anyone from the wrath of Allah. Al-Nawawi (may Allah have mercy on him) said: 
Whoever dies in kufr will be in Hell and his blood ties will not benefit him at all. Sharh Saheeh Muslim, 3/79. 
The ruling on the parents and grandfather of the Prophet (peace and blessings of Allah be upon him) is no exception to that. The father of Ibraaheem (peace be upon him) was a kaafir and remained so until he died, and Ibraaheem disavowed himself of him, as Allah says (interpretation of the meaning): 
“And Ibraaheem’s (Abraham) invoking (of Allah) for his father’s forgiveness was only because of a promise he [Ibraaheem (Abraham)] had made to him (his father). But when it became clear to him that he (his father) is an enemy of Allah, he dissociated himself from him”
[al-Tawbah 9:114] 
The Prophet (peace and blessings of Allah be upon him) even stated this clearly, when the following verse was revealed (interpretation of the meaning): 
“And warn your tribe (O Muhammad) of near kindred”
[al-Shu’ara’ 26:214]
He said: "O people ofQuraysh (or said similar words)! Buy (i.e. save)yourselves (from the Hellfire) as I cannot save you fromAllah's punishment. O Bani Abd Manaaf, I cannot saveyou from Allah's punishment.  O ‘Abbaas ibn ‘Abd al-Muttalib, I cannot saveyou from Allah's punishment.  O Safiyyah, aunt ofthe Messenger of Allah, I cannot save you from Allah'spunishment. O Faatimah daughter of Muhammad, Ask me for whatever you want of my wealth, but I cannot save you from Allah's punishment.” 
Narrated by al-Bukhaari, 2753; Muslim, 206. 
No Muslim should let his feelings for the Messenger of Allah (peace and blessings of Allah be upon him) and his relatives make him issue judgements without clear proof and knowledge, lest that lead to loss in this world and in the Hereafter. And Allah is the One Whose help we seek.