4 Royal baby collectables

1. A pair of Crown Ducal transfer-printed bone china mugs - £120-£180

Memorabilia featuring key members of the Royal family as children is particularly popular with collectors.

These 1937 transfer-printed bone china mugs commemorate the births of Princess Elizabeth (left) in 1926, and Princess Margaret (right) in 1930. The mugs feature portraits taken by photographer Marcus Adams and were produced on the event of George VI's and Queen Elizabeth's (Elizabeth and Margaret's parents) coronation.

2. Royal Doulton bone china plate - £45

This 1982 Royal Doulton bone china plate commemorates the birth of Prince William to the Prince and Princess of Wales. It is 8in (20.5cm) in diameter.

The new royal arrival will undoubtedly mean a boom in commemorative ware from tea towels to egg cups. Judith Miller of Miller's Antiques says: "If you're collecting for investment purposes, stick to good quality pieces in small limited editions by high-quality makers, such as Wedgewood or Doulton."

3. Coronet Pottery 'The Ladies of August' commemorative plate - £40-£55

This 1990 plate features portraits of Queen Elizabeth, the Queen Mother, Princess Margaret and Princess Anne. These three members of the Royal family have birthdays in August. It is 10.5in (26.5cm) in diameter.

4. A pair of Royal Crown Derby bone china miniature love cups - £65-£75 each

These were made to commemorate the births of Prince William in 1982 and Prince Harry in 1984.

Rarity is a factor that pushes up the price of earlier Royal birth memorabilia: "Lots was produced for Prince Williams's birth but people weren't so interested second time around meaning Harry mugs can fetch £6 to £60 today," says Ron Smith of royal memorabilia specialist Commemorabilia.co.uk.

"Look for items with the new prince/princesses' name and date of birth, made in Britain by makers with a Royal patent. Also collect something you like," he adds.