I am 9 yrs old and I love mythbusters. I bought a toy convertible at walmart and I was curious if this could really be true.

Not safely. If the trailer is larger than the tow vehicle, it can start swaying and cause the whole rig to run off the road. I've seen two accidents like this; both were rollovers. One was a small car pulling a trailer with an old Jaguar sedan. Another was a Jeep Cherokee pulling a big enclosed trailer.