Mum, Erin Rushton, aged 29, bought rabbits named Lola, Bonni and Doc at the start of lockdown for her children.
And the bunnies, who live with her, have since gained a reputation for their mischievous antics.
The furry trio love the company of humans and are always interested in who comes knocking throughout the day.
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And Erin says she was left in stitches when she received a note from her postman earlier this month, explaining where he left her parcel.
The note read: “Cupboard side of house. Killer bunnies guarding!” with a smiley face at the end.
Posting the encounter on Facebook, Erin said: “I have three free roaming bunnies who can go anywhere in the garden and who love visitors.
“They are super friendly and will come bounding down to the gate when they see it open.
“I can only imagine what the poor postman had to put up with when he came in!”
And she added: "The bunnies are therapy animals and I originally bought them for my daughter to help with her anxiety.
“They're always keen to say hello to anyone who comes and visits and I can imagine the postman had them run around his feet when he came by.
“Whether it's the DPD or the milkman - when they hear the side gate rattle they're there in a flash to greet them.
“The note was hilarious - it really made my afternoon!”
Her post has since garnered 4,000 reactions, with over 2,000 laughing emojis.
One wrote: “Killer bunnies! But they’re so cute!”