How children will be reunited with their parents in Paradise.

Parents will be delighted to see their children in Paradise.

How children will be reunited with their parents in Paradise.

 Parents will be delighted to see their children in Paradise.

If the children of those who will enter Paradise in the Hereafter also die as believers and enter Paradise, then Allah will gather them together in Paradise. This is one of the blessings and rewards of Paradise. Even if the deeds of the children are few, if they are behind in the level of status in Paradise, then Allah will raise their status by His mercy and take them to their parents. Allah says,

وَ الَّذِیۡنَ اٰمَنُوۡا وَ اتَّبَعَتۡهُمۡ ذُرِّیَّتُهُمۡ بِاِیۡمَانٍ اَلۡحَقۡنَا بِهِمۡ ذُرِّیَّتَهُمۡ وَ مَاۤ اَلَتۡنٰهُمۡ مِّنۡ عَمَلِهِمۡ مِّنۡ شَیۡءٍ ؕ كُلُّ امۡرِیًٴۢ بِمَا كَسَبَ رَهِیۡنٌ

And those who believe and their children follow them in faith, we will reunite them with their children, and we will not diminish from them any of their deeds. Every person will be responsible for what he has earned. (Surah At-Tur: 21)

In explaining this verse, Abdullah ibn Abbas (may Allah be pleased with him) said Allah will raise the children of the righteous believers to the level of their respected fathers, even if they do not deserve that level in terms of deeds—so that the eyes of the parents will be refreshed by having children.

they are in a separate place in Paradise.

The people of Paradise will enter Paradise and ask about their parents, wives, and children: Where are they? They will be told that they have not reached your level of status. Therefore, they are in a separate place in Paradise. This person will pray, O Allah! In this world, I did deeds for myself and for all of them. Then Allah will command that they should be placed together in this level of Paradise.

In another place in the Quran, Allah Almighty says,

وَ الَّذِیۡنَ صَبَرُوا ابۡتِغَآءَ وَجۡهِ رَبِّهِمۡ وَ اَقَامُوا الصَّلٰوۃَ وَ اَنۡفَقُوۡا مِمَّا رَزَقۡنٰهُمۡ سِرًّا وَّ عَلَانِیَۃً وَّ یَدۡرَءُوۡنَ بِالۡحَسَنَۃِ السَّیِّئَۃَ اُولٰٓئِكَ لَهُمۡ عُقۡبَی الدَّارِ جَنّٰتُ عَدۡنٍ یَّدۡخُلُوۡنَهَا وَ مَنۡ صَلَحَ مِنۡ اٰبَآئِهِمۡ وَ اَزۡوَاجِهِمۡ وَ ذُرِّیّٰتِهِمۡ وَ الۡمَلٰٓئِكَۃُ یَدۡخُلُوۡنَ عَلَیۡهِمۡ مِّنۡ كُلِّ بَابٍ

Those who are patient, seeking the pleasure of their Lord, and establish prayer, and spend out of what We have provided for them, secretly and openly, and repel evil with good deeds, for them is the best end of the Hereafter. That is, the Garden of Eternity, which they will enter. And so will their fathers, their wives, and their children, who did good deeds. And the angels will come to them from every gate, welcoming them. (Surah Ar-Ra'd: 22, 23)

These two verses also indicate that those who believe and do good deeds in this world, Allah Almighty will grant them Paradise and will join their believing relatives with them there. If someone's status is low, Allah Almighty will raise his status by His grace upon the request of his relatives.

This will happen only to those who believe.

 If the father, mother, children, other relatives are disbelievers, they will not be allowed to enter Paradise.

In another place in the Quran, the angels carrying the Throne pray for the believers that Allah may grant them Paradise and join their righteous parents and children with them. Allah says,

اَلَّذِیۡنَ یَحۡمِلُوۡنَ الۡعَرۡشَ وَ مَنۡ حَوۡلَهٗ یُسَبِّحُوۡنَ بِحَمۡدِ رَبِّهِمۡ وَ یُؤۡمِنُوۡنَ بِهٖ وَ یَسۡتَغۡفِرُوۡنَ لِلَّذِیۡنَ اٰمَنُوۡا رَبَّنَا وَسِعۡتَ كُلَّ شَیۡءٍ رَّحۡمَۃً وَّ عِلۡمًا فَاغۡفِرۡ لِلَّذِیۡنَ تَابُوۡا وَ اتَّبَعُوۡا سَبِیۡلَكَ وَ قِهِمۡ عَذَابَ الۡجَحِیۡمِ رَبَّنَا وَ اَدۡخِلۡهُمۡ جَنّٰتِ عَدۡنِۣ الَّتِیۡ وَعَدۡتَّهُمۡ وَ مَنۡ صَلَحَ مِنۡ اٰبَآئِهِمۡ وَ اَزۡوَاجِهِمۡ وَ ذُرِّیّٰتِهِمۡ اِنَّكَ اَنۡتَ الۡعَزِیۡزُ الۡحَكِیۡمُ

Those who bear the throned those around it glorify the praise of their Lord and believe in Him. And they ask forgiveness for the believers, saying, ‘Our Lord, You encompass all things in mercy and knowledge. So forgive those who repent and follow Your way. And save them from the punishment of Hell. Our Lord, and admit them to the Garden of Eternity, You have promised them. And those who do righteous deeds among their parents, their pouses, their children. Indeed, the Almighty, the Wise.’ (Surah Ghafir: 7-8)