January 12, 1954:
The first one is more an observational strip about human nature than Lucy's personality specifically, although we might conclude that she's been somewhat spoiled by her tremendous winning streak at Checkers against Charlie Brown. The second is a more typical strip about sisterly concern, but it does give three more of those great serif'd sleeping Zs.
(I should note that, despite what the title of this post might lead you to conclude, Lucy and Linus' last names have not been revealed in the strip yet. Or if they have, I certainly don't remember it happening.)
