December 11, 1953: World-shaking calamity

Read this strip on gocomics.com.

This is a bigger deal to Charlie Brown than the rest of us because such a large percentage of his hair is disarranged.  (75%, that one on the back of his head passed unmolested.)

This does seem to make it clear that Charlie Brown has exactly four hairs.

March 26, 1952: That's just-- an alibi!

It's Lucy's first strip with characters other than Charlie Brown or her unseen father. The girl looks pretty miserable in the second panel, doesn't she?

Also of note here, it's Violet's first strip with her hair done in a ponytail, probably done so she doesn't look so much like Lucy.