Auckland's equine twins doing well at 21 days

Owner Gayle Lawrie says the pair are eating some solid food now and are growing by the minute.

The pair's 14-year-old old thoroughbred mother, Tarn, is also faring well in caring for her two offspring and, according to Gayle, is very protective of them.

Holly and Rio were born around dawn on Christmas Day.

Gayle was understandably surprised to discover another head and two feet emerging from Tarn after the birth of Rio.

After about 10 hours of special care and some bottle-feeding and help with balance, the pair were learning the basics of standing up and feeding from mum. Three weeks later, they're bolder and brassier than ever.