Maybe at first it looks like the grandmother and the child are getting along while they're making jokes from the almanac, but we quickly see they're a million miles away from one another. They're the only ones home, and maybe the only two who even live in the house. The grandmother has some secret sadness that she keeps from the child, and the child, probably sensing this sadness and distance from her grandmother, turns to her imaginative drawing to escape the loneliness. Sure, the two seem to get along just fine, but we can't help but feel that they're too far apart from one another to really be a happy family.
They're not lonely! They have each other. Sheesh.
The grandmother's sadness has nothing to do with loneliness. She's bummed about something else entirely.