How early did the word 'Muppet' come into general use in American English? Soon enough that it would be a plausible nickname for a baby (boy) born in 1975? There is an older child in the family, so the parents would be aware of children's TV.
ETA: It's a pre-birth nickname I was planning on, to save them picking a name before they know the sex. So it would be pre-Muppet Show. Would Sesame Street have given enough exposure to the term itself rather than the things?
ETA2: What about alternatives? Muffin? Or is that too twee for a boy?