By Lydia Warren PUBLISHED: 13:19 EST, 3 April 2013 | UPDATED: 06:42 EST, 4 April 2013 A Missouri family is celebrating giving birth to rare identical triplets, bringing their family to seven. But two weeks after the arrival of their daughters - Sonja, Sylvia and Scarlett - on March 19,  Laura and Brad Partridge are still unable to tell the girls apart, so they have devised a nifty plan. 'Everyone has a signature colour,' Laura, from Des Peres, told MailOnline. 'Pink for Scarlett, purple for Sylvia and yellow for Sonja, and they have corresponding outfits. 'A friend is even getting me non-toxic nail polish for their toenails so that way we know for sure who's who in the middle of the night or during a bath.'
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Estimates for the chances of giving birth to identical triplets range from one in 60,000 to one in 200 million
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The births mean that the Partridge family, from Des Peres, Missouri, now have five children aged three and under
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