Verse 19

وَجَآءَتْ سَيَّارَةٌ فَأَرْسَلُوا۟ وَارِدَهُمْ فَأَدْلَىٰ دَلْوَهُۥ قَالَ يَـٰبُشْرَىٰ هَـٰذَا غُلَـٰمٌ وَأَسَرُّوهُ بِضَـٰعَةً وَٱللَّهُ عَلِيمٌۢ بِمَا يَعْمَلُونَ

And a caravan was passing by, they sent their water bearer, and he lowered his bucket, he said, good news here is a boy. They kept him hidden as part of their belongings. And God knew full well what they were doing.