The children of the Believers who die before reaching the age of puberty will be in Paradise, In Sha Allah, by the Grace and Mercy of Allah. He (swt) says:
“And those who believe and whose offspring follow them in faith – to them shall We join their offspring, and We shall not decrease the reward of their deeds in anything. Every person is a pledge for that which he has earned” [52:21]
‘Ali ibn Abi Taalib understood this aayah – “Every person is a pledge for what he has earned” [74:38] – to indicate that the children of the believers would be in Paradise, because they did not earn anything for which they would be considered a pledge. [at-Tadkhirah, p. 511]
al-Bukhaari included a chapter in his Saheeh entitled “The virtue of one whose child dies and he bears it with patience for the sake of Allah”, in which he quoted the hadith of Anas who said that, “A Muslim whose three children die before reaching the age of puberty will be admitted to Paradise by Allah out of Mercy towards them.”
According to a hadith narrated by Abu Sa’eed the women asked the Prophet (Saw) “Set aside a day for us”. So he preached to them and said, “Any woman whose three children die will be shielded from the Fire by them.” A woman asked, “What about two?” He said, “And if two [die].” [Saheeh al-Bukhaari, Kitaab al-Janaa’iz, Baab fadl man mata lahu walad fa ahtasaba, Fath al-Baari, 3/118]
According to a hadith narrated by al-Baraa’ (saw), “When [the Prophet’s son] Ibraaheem, died, the Messenger of Allah (saw) said, “There is a wet nurse for him in Paradise””. [Saheeh al-Bukhaari, Kitaab al-Janaa’iz, Baab ma qila fi awlaad al-Muslimeen, Fath al-Baari, 3/244]
The conclusion that may be drawn from this hadith is that the children of the believers will be in Paradise as Ibn Hajar says, “The one who is the reason for his parents being shielded from the Fire should be protected himself, because he is the means and cause of mercy”. [Fath al-Baari, 3/244]
A number of reports clearly indicate this for example, “The Muslims and the children will be in Paradise” [narrated by ‘Ali, quoted by ‘Abdullaah ibn Ahmad in Ziyaadat al-Musnad]
“A Muslim couple whose three children die before reaching the age of puberty will be admitted by Allah to paradise, they and their children, by His Grace and Mercy” [Fath al-Baari, 2/245]
From Abu Hurayrah that the Messenger of Allah (saw) said: “Their little ones are the pageboys of Paradise. One of them will meet his father – or his parents – and take hold of his clothes – or his hand – just as I am taking hold of the hem of your garment, and he will not let go” Or he said,” And he will not let go until Allah admits him to Paradise.” [Silsilat al-Hadith as-Saheehah, 1/184, no. 342]
“The children of the believers will be in Paradise, being cared for by Ibraaheem and Sarah until they give them back to their parents on the Day of Resurrection”. [narrated by Abu Na’eem, ad-Daylami and Ibn ‘Asaakir from Abu Hurayrah – Silsilat al-Hadith as-Saheehah, 3/451 no. 1467; see also 2/156 no. 603 narrated by Ahmad, Ibn Hibbaan, al-Haakim]
an-Nawawi referred to the ijmaa” of reliable Muslim scholars that any Muslim child who dies will be in Paradise. [Fath al-Baari, 3/244]. al-Qurtubee stated that Hammaad ibn Zayd, Hammad ibn Salamah and Ishaaq ibn Rahawayh refrained from giving an opinion [at-Tadhkirah, p.511]. an-Nawawi said, “Some of them refrained from giving an opinion because of the hadith of ‘Aaishah which was reported by Muslim with the wording, “A boy of the Ansaar died, and I said, “It is good for him, because he did not do or know any evil”. The Prophet (saw) said, “You should not say that because Allah (swt) has created its own people for Paradise..” The response to that is that he was most likely rebuking her for hastening to say something so decisive with no proof, or else he said that before he knew that the children of the Muslims would be in Paradise.” [Fath al-Baari, 3/244].
I suggest that the best opinion is that this hadith indicates that it is not permitted to state definitely that any one particular person is one of the people of Paradise, even if we know that in general they will be in Paradise.
The second point is that we should not be hasty in such matters, so that people will not dare to do what happens so often nowadays, when the bereaved claim that their departed loved one is in Paradise, even though he was the worst of people.