What is the figure of speech in ' Laugh and be mERRY'?

The phrase "Laugh and be mERRY" employs a form of Wordplay known as alliteration, where the initial consonant sounds of "laugh" and "merry" both start with the letter 'm' sound, creating a rhythmic quality. Additionally, it can be interpreted as a form of anaphora, as both Words convey a sense of joy and positivity. The overall effect emphasizes the connection between laughter and happiness.