It's amazing how two pets can become of one mind. Sometimes they spontaneously decide to do the identical thing, but other times it's one leading the way and the other following. However it comes about, it makes for sweet photos.

Here are our cover-bookends, Trudy and Molly. How do you tell the difference between them? Well, there are tiny but crucial differences in their topographical forehead maps.

Brina and Sammy have a parent-and-child similarity. The two Bernese Mountain Dogs could prop up a whole bookshop, not just a shelf of books.

Casper and Charli are aligned but independent.

There's no flame in the fire, but French Mastiffs Milly and Dodge nap in symmetry anyway. Meanwhile, at the smaller end of the canine scale, mum and daughter Tara and Cara strike the same angle. (Hope they don't always lean like that.)

Islay and Bailey are cheek to cheek.

Monty and Bella are sleeping in step.

Rusty and Breeze back each other up.

Nige and Bella are brother and sister whose affection cooled not long after this photo was taken. Funny thing, families.

Here's a competitive display of synchronised sulking by Murphy Brown and Bailey. (Notice the maximised impact on foot traffic.) The brace of dappled tummies on the right belong to Hudson and Mississippi; if you think those two mighty river names are a loose fit, then be reassured that these two are also known as Huddy and Missy.

Floor ballet, performed by Maggie and Lucy (left) and Rocky and Bella.

Gypsy and Chee-Chee are an almost-matching pair.

All smiles: Willow and Jack.

All hair and whiskers: Zorro and Li'l Fluff.

All sweetness and mischief: Ed and Ruby. This pair of former laboratory Beagles were adopted early this year, at about four months of age. Owner Sarah says: "Bonding took a bit longer with them both since they hadn't had a lot of interaction with humans other than to be fed - from birth they'd been kept in an outdoor caged enclosure with their siblings. I think it also took a bit longer for them to bond with us since they had each other. But they've now settled in well and both love to sit on my lap (together!) in the evenings." With each other and their caring owners, Ed and Ruby will never be lonely.

An Irish Setter yin-yang pattern: Heather and Holly.

Distinct looks but sharing the same spirit - Jock and Tom. Tom is still going strong at 13, but RIP Jock.

Fresh from the barber and hitting the classic bookend pose are Bella and Moose. The two Bichon Shih Tzu crosses are half-siblings.

Neuro and Oli sleep in chronological order. (I'm not sure if they start on the right, or on the left.)

Brothers Smokey and Fluffy scan the horizon for their dad to return. Smokey died a year ago, but Fluffy's still trucking at 13. Meanwhile, Betty and Bugs guard the beer. RIP Bugs.

Skye and Whisky form their own repeating pattern.

Here you go - two full sets of bookends. Michele sent us this photo of her Irish Wolfhound Georgia along with Georgia's niece, nephew, and their dad. Beautiful, but that's an awful lot of mud...

Finally, tiny bookends Rosalie and Emmet defy you not to join them in a huge almost-weekend yawn.

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