The clip comes from a Vine posted in 2014, where a young boy filmed himself in the passenger seat of his mother's car and delivered the line in a strong British accent. Vine's short loop format helped the phrase spread quickly, and it was remixed, quoted and reenacted across YouTube and social media after the platform closed. The follow up line get out me car became part of the same joke. It remains popular because the wording, accent and engine sound are instantly recognisable even without the original video.
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Child's voice clip saying I'm in my mum's car followed by broom broom, from the viral Vine meme used for funny driving and getaway reactions online.
This is the short voice clip of a young British boy proudly announcing he is in his mum's car, followed by his own broom broom engine impression. The delivery is cheerful, high pitched and completely deadpan, which makes the boast feel funnier the more serious he sounds. It lasts just over a second, so the joke lands instantly without any setup. Viewers recognise the line immediately and use it as a shorthand for a proud, silly getaway or for showing off something very ordinary as if it were impressive.