Is "Pray for him who knelt to comfort a child whose bird had died" correct?

The story of the Prophet Muhammad's ﷺ consolation of the boy whose bird died is well-established in the two Sahih collections, but there is no mention in its narration of the Prophet ﷺ sitting on his knees. The Prophet ﷺ entered upon a younger brother of Anas, saw him sad over the death of his bird with which he used to play, and asked him: "O Aba Umayr, what did the little bird (Nughayr) do?" The Nughayr is a bird similar to a sparrow, with a red beak.