Peanuts by Charles Schulz for September 17, 1958
Transcript:
Linus, dragging his blanket, approaches Charlie Brown. Charlie Brown asks, "Still got your blanket, Eh, Linus?"<br> <br> He continues, "What are you going to do when you get too old to drag it around?"<br> <br> Linus looks at his blanket and says, "Who knows?"<br> <br> He continues, "I've been thinking seriously of having it made over into a sport coat!"<br> <br>
Later on, Snoopy does that for him.
https://www.gocomics.com/peanuts/1971/11/10