Keep in mind, he was pretty young; I'm not saying we're all exempt from grief (would be nicer, tho), but for such a young child, they're conflicted inside - their main caretaker and companion is suddenly ripped away, forcing them to forego a possibly dangerous journey to a place they don't even know... O_o Still, the worst scene of that sequence is when he sees the shadow and he thinks it's her, and he gets all excited and runs up to it and licks it, and then.... *sniff*
Momma Longneck, give the child a break!!