It is narrated from Hazrat Anas bin Malik, may Allah be pleased with him, that the Prophet, peace and blessings be upon him, said: When the people of Paradise will enter Paradise, there will still be some space left in Paradise. Allah will create another creation for it and fill Paradise with them.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 12541