RARE twin calves have been born on the National Trust’s Greenlands Farm, part of the Purbeck estate.

The red Devon calves are being taken care of by Lisa Hawthornthwaite who hit the headlines in 2008 when she became Britain’s only cowgirl, looking after a herd of 30 cattle that roams the Purbeck heathland.

The latest additions to the herd have been named Clover and Bob by Lisa’s daughter Charlotte, aged nine.

It is rare for cattle like proud mum Ellabella to give birth to twins and Lisa had no inkling that anything unusual was going on until the second calf arrived.

“We’ve never had a set of twins at Greenland Farm before so this is a new one on us,” said Lisa.

“We only thought she was having one calf and then within an hour she popped the other one out. We had no warning at all.”

Despite early fears Ellabella might reject one of the youngsters the new family now seems to be doing well. The calves will spend their first week indoors while Lisa makes sure Ellabella is able to provide them with enough milk.

All being well, they will then move out into a field near the farm buildings until they are old enough to join the main herd.

Clover and Bob can look forward to a life roaming Studland and Godlingston Heath helping the National Trust maintain the fragile habitat – home to rare species such as sand lizards and the Dartford warbler.

Grazing is a traditional method of heathland management and helps keep invasive scrub under control.

Lisa already has plans to train Clover and Bob to walk on a halter so they can be taken to areas not accessible by vehicles to carry out selective grazing tasks.

“These two will be here for the whole of their life I expect, so they have got a nice life ahead of them,” she added.