Poetry and tradition

I was reading Kindred in Death. At the end, there's a wedding and I came across something about the bride having "something borrowed and something blue". Then I remembered in Breaking Dawn, Bella's marriage also stating "something new, and something old". Makes me wonder, What's this? I google and found it! ^^ It's a wedding tradition in western countries, originating probably from the Victorian Era in England.

Something old, something new,

Something borrowed, something blue,

And a silver sixpence in her shoe.

Something Old--symbolizes the continuous chain between the the bride's family and the past.
Something New--symbolizes optimism and hope for good fortune and success in the brides new life.
Something Borrowed--symbolizes the friends and family that will always be there for the bride and the shared happiness from married couples. 

Something Blue--symbolizes the bride's faithfulness, loyalty, purity, fidelity and purity.