How could I forget Princess Margaret?!
HRH The Princess Margaret, Countess of Snowdon
Elizabeth's Label was very similar to a number of Princesses Royal but, instead of a red Rose between two St George's Crosses, she received a central Tudor Rose. (As her aunt, HRH The Princess Mary, Countess of Harewood was still alive into her niece's reign, Elizabeth was never created Princess Royal as there is no tradition of Dowager Princess Royal in the UK.) The relevance of Elizabeth's Label is that Margaret's was based on the reverse arrangement.
However, instead of what would then have been a central St George's Cross, Margaret was assigned a Thistle in honour of her Scottish heritage on her mother's side and for the fact that she was born at her maternal family's seat of Glamis Castle in Scotland.
The resulting two Tudor Roses were quite fortuitous for Margaret. The Princess was named Margaret possibly in honour of both St Margaret, an 11th Century Queen of Scotland who had fled England with her brother Edgar Ætheling after the Norman Conquest and married King Malcolm III, and Margaret Tudor, daughter of King Henry VII, who had married King James IV of Scotland and thereby became grandmother to Mary, Queen of Scots. Princess Margaret's middle name was Rose, named after her maternal aunt, Rose Bowes-Lyon who became Countess Granville and was Margaret's godmother.
Princess Margaret's Label is therefore a pun on her middle name.