ENOfficial
Ibn 'Umar reported that when his children had reached puberty and he had withdrawn to his room, none of them entered where he was except with his permission.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا مَطَرُ بْنُ الْفَضْلِ، قَالَ: حَدَّثَنَا يَزِيدُ بْنُ هَارُونَ، عَنْ هِشَامٍ الدَّسْتُوَائِيِّ، عَنْ يَحْيَى بْنِ أَبِي كَثِيرٍ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّهُ كَانَ إِذَا بَلَغَ بَعْضُ وَلَدِهِ الْحُلُمَ عَزَلَهُ، فَلَمْ يَدْخُلْ عَلَيْهِ إِلا بِإِذْنٍ.
sunnah.com