I do. I tested their object
permanence with a RUBBER duck,
The Big Bang Theory Season 12, Episode 17
I've bounced many a RUBBER ball
in my day.
The Big Bang Theory Season 5, Episode 17
Like when it turns out
she's made of RUBBER,
The Big Bang Theory Season 7, Episode 20
If you really want to help,
put on a RUBBER glove,
The Big Bang Theory Season 11, Episode 16
And RUBBER gloves, air freshener...
The Big Bang Theory Season 8, Episode 19