Skandapurana 5.21.75

5.21.75

putreṇa sahitaḥ paścādārādhaya divāniśam..
vayameva tvayā sārdhaṃ taṃ ca devaṃ pitāmaham..75..

Together with your son, worship [him] afterwards day and night. / We ourselves, along with you, [shall worship] that god, the grandfather;