Adam Clarke on John 21:5

Children - Παιδια, a term of familiarity and affectionate kindness: it is the vocative case plural of παιδιον, which is the diminutive of παις, and literally signifies little children, or beloved children. How the margin has made sirs out of it I cannot conceive.

Any meat - Προσφαγιον from προς, besides, and φαγω, I eat; any thing that is eaten with bread, or such like solid substances, to make the deglutition the more easy: here it evidently means any kind of fish; and our Lord seems to have appeared at first in the character of a person who wished to purchase a part of what they had caught: see the note on Joh 6:9.