According to a letter from his physician, placed in the Archives of the Charles M. Schulz Museum by his widow, Schulz had essential tremor, a condition alleviated by beta blockers.
Menurut sebuah surat dari dokternya, yang ditempatkan di Archives of the Charles M. Schulz Museum oleh jandanya, Schulz memiliki tremor esensial, suatu kondisi yang dikurangi dengan beta blockers.