You saw me lying stretched out in front of the Messenger of Allah ﷺ while he was praying. When he wanted to prostrate, he would tap my leg, so I would draw it in, and then he would prostrate.
أخبرنا يعقوب بن إبراهيم قال حدثنا يحيى عن عبيد الله قال سمعت القاسم بن محمد يحدث
لقد رأيتموني معترضة بين يدي رسول الله ﷺ ورسول الله ﷺ يصلي فإذا أراد أن يسجد غمز رجلي فضممتها إلي ثم يسجد
Bukhari narrated it in Kitab al-Salah, in the chapter "Should a man nudge his wife during sujud so that she may prostrate?", hadith no. 519, from the hadith of Yahya Qattan through this same chain. It is also found in Al-Kubra, hadith no. 157.