Is the older child also his son?
So, at the beginning Macbeth and Lady Macbeth are burying their toddler-age son, and has been discussed by others, the theme of their childlessness is central to the how the text is interpreted here.
I wondered if others felt it was implied that the older boy (I'd say 13/14/15?) who dies in the opening battle is also their son? Macbeth seems very tender with him before the battle, and then the way Macbeth handles his corpse (particularly the stones on the eyes, which no other corpse gets) mirrors very closely the treatment of the young son's body. The boy then appears in Macbeth's visions, and, again, when he sees him in the second witches' prophecy vision he caresses his face (and I think kisses him?) again implying a close relationship.
If the older boy was also their son, and died fighting for Malcolm, who had called in boys too young to fight in his desperation, I think it would make some of Macbeth's actions, and his descend into madness, even more poignant in this particular interpretation.
Might just be me though!