Bet Your Sweet Bippy informal
To show that you're certain about something
You bet your sweet bippy I'm going to get the first prize!
A: "Can you come tonight?" B: "You bet your sweet bippy I can!"
You can bet your sweet bippy that he's going to lose again.
Meaning absolutely certain or without a doubt
Another way to say "absolutely", "definitely" or "for sure"
Totally certain.
With absolute certainty; decisively
You can be absolutely certain that something is true or will occur.
The expression originated from the show called Laugh-In in the late 1960s. At that time, TV shows had strict guidelines about which words they were allowed to say. The show writers have chosen the substitution "bippy" to get around censorship. Show creators claimed that the word was a nonsense word that they picked just because it sounded funny. The phrase became popular since then.