Late in the sixth season in "We're Going to Disney World," Steve transformed into Stefan as part of an inventor's competition at
Walt Disney World; however,
Laura sabotaged the transformation chamber to prevent him from turning back into Steve. During his extended stint as Stefan, he proposed to Laura in front of Cinderella Castle. Laura accepted, but their engagement was broken off when Myra appealed to Stefan and Laura revealed her sabotage.
While just about everyone liked Stefan, Myra disliked him immensely, believing he was a joke and knows that her "Steviekins" was perfect already.
In the seventh season finale "Send in the Clones," Steve created a cloning machine and wound up cloning himself. Myra was initially excited, but eventually realized that two Steves were just too much.
To clear up the situation, Laura proposed that one of the Steves be permanently turned into Stefan, so that she and Myra can both be with the one they love.