Near Rhymes (Slant Rhymes):
* lesson
* blessin'
* question
* session
Eye Rhymes (Words that look like they rhyme but don't sound the same):
* prison
* poison
Other Options:
* future (if you're talking about the futuristic theme of the Jetsons)
* space (if you're referencing their space age lifestyle)
* flying (if you're referring to their flying cars)
Ultimately, the best rhyming word will depend on the context of your poem or song.