Brahmā, who was not born of a material source but of the lotus flower coming out of the navel abdomen of the Lord, is the creator of all those who are materially born. Of course, by the grace of the Lord, Brahmā was able to see the form of the Lord.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
अजः सृजति भूतानि भूतात्मा यदनुग्रहात् । ददृशे येन तद्रूपं नाभिपद्मसमुद्भवः
ajaḥ sṛjati bhūtāni bhūtātmā yadanugrahāt | dadṛśe yena tadrūpaṃ nābhipadmasamudbhavaḥ
SB 2.8.9