With one weighing in some six times heavier than another, they may have seemed like an ill-matched pair.
But these two Hermann's tortoises are twins, which hatched together from the same egg.
Nicknamed Arnie and Danny – after the stars of the 1988 film Twins, which stared Arnold Schwarzenegger and Danny DeVito as an unlikely pair of twins – one weighed 12g when it was born a month ago, while its little sibling was just 2g.
Since then, the smaller one – which is now around the size of a 10p piece – has been receiving some special TLC to build up its strength and size.
Barbara Ashford, 52, from Litcham, near Dereham, carefully watched over it during a three-week stint in an incubator.
'I was having to break up her food for her which I'd never done with any of the other hatchlings, but I'm so happy as she's just started to eat,' she said.
'She was so small, it was touch and go for a while. Nine out of 10 twins don't hatch or one is dead, they are quite rare.'
Mrs Ashford has kept tortoises for 17 years and bred them for 15 years. She said she had only come across one set of twins prior to this.
She said she not officially named them yet, as she did not want to get too attached to them.
Although they have attracted the nicknames Arnie and Danny, their sex will not be known until they are older. However, the eggs were incubated at a temperature which usually produces females.
When they were born, the pair were still linked by an umbilical cord, which separates over time.
Her love of the shell dwellers began when her husband brought her a Horsefield tortoise, called Tabitha, when her eldest son left home.
Mrs Ashford, said: 'The more I began to breed them, the more involved I got.
'I have been to Holland for a conference on how to keep tortoises in that area and on a field study trip to Morocco to see if there were any wild tortoises left.'
Hatching hundreds of little ones throughout the years, the secret to successful breeding is getting to grips with the adult female. 'They will only lay when she finds somewhere she wants to, or she just won't.
'Conservation is so important as they're so endangered. We sell the babies to people setting up breeding groups.'
If you have an animal story, email jemma.walker@archant.co.uk
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