SB 10.85.47
sri-bhagavan uvaca
asan mariceh sat putra
urnayam prathame ’ntare
devah kam jahasur viksya
sutam yabhitum udyatam
Translation:
The Supreme Lord said: During the age of the first Manu, the sage Marici had six sons by his wife Urna. They were all exalted demigods, but once they laughed at Lord Brahma when they saw him preparing to have sex with his own daughter.