The Prophet (ﷺ) brought his grandchildren to the Masjid, and they climbed on him, etc; so it is permissible to bring them to the Masjid. That the Prophet (ﷺ) was merciful and kind towards the children.

It is very important to raise our children with a strong attachment and love for their religion, and community, and thus it is important for them to have a strong and positive attachment to the mosque from a young age, especially in non-Muslim environments.

“In Turkey, after teraweh, children are invited to play with the Imam. So that they are happy to go to the mosque. Even some new mosques in Turkey such as the Hamdi Cami mosque in Ankara have a playground in the mosque in the lower right corner of the stairs. If the mosque does not have a place to play inside, it is prepared outside the mosque like a garden. The mosque became the Center of happy people.

They seem to believe in what their predecessor, Sultan AlFatih, commanded that, "Be worried if your mosque no longer hears the voice of a child".