Spike, Snoopy's older brother who lived in the desert, was the most frequently seen sibling in the strip. He was introduced in the August 13, 1975, strip. He was a recurring character between 1984 and 1988, and was also used in one-off appearances sporadically through the rest of Peanuts history. Spike is named after Charles Schulz's childhood dog.
appearance is similar to Snoopy's, but he is substantially thinner, has a perpetually sleepy-eyed look, sports long, droopy whiskers that look like a mustache, and wears a fedora. He is called Snoopy's older brother during the first story in which he appears. Spike lives in the middle of a desert near Needles, California, mostly interacting with inanimate saguaro cacti and rocks.
Belle is Snoopy's sister, who first appeared in the strip on June 28, 1976 She lives in Kansas City, Missouri with her teenage son, whom Snoopy noted as resembling the Pink Panther. Belle herself bears a strong resemblance to Snoopy, but with longer eyelashes. In addition, she wears a lace collar and sometimes wears a pearl necklace.
Belle only made a few appearances in the strip but is remembered because of the Belle stuffed animal toys sold in the late 1970s and early 1980s. San Francisco toy merchandiser Determined Productions had the license to make Snoopy plush toys, and they introduced Belle plush after receiving many requests from children who wanted a female "sister" doll.