Porta Fortuna is the first foal and so far only winner of Too Precious (Holy Roman Emperor), who won four races on the all-weather at Dundalk at up to 1m4f. Too Precious is a full sister to Numerian, a triple Group 2 winner in Australia who was second in the Gr.1 Australian Cup, and to Montesilvano, a winner placed in the Gr.3 Prix Francois Boutin.

Second dam Delicate Charm (High Chaparral) was unraced and is a half-sister to Another Nation (Revoque), placed at Group 3 level over hurdles.

Third dam Kantikoy (Alzao), also unraced, is a half-sister to Kithanga (Darshaan), winner of the Gr.3 St Simon Stakes and third in the Gr.1 Irish St Leger. Kithanga is the dam of Milan (Sadler's Wells), winner of the Gr.1 St Leger and later a champion jumps sire, and of Koora, who also won the Gr.3 St Simon Stakes. Her grandchildren include Kemari, winner of the Gr.2 Queen's Vase, Klondike, winner of the Gr.3 Prix de Reux, and the sire Karpino, winner of the Gr.2 German 2000 Guineas.

This is also the family of Kahyasi, who won the Gr.1 Derby and the Gr.1 Irish Derby before becoming a sire, and of Key Change (Darshaan), winner of the Gr.1 Yorkshire Oaks.

Too Precious has a 2-year-old filly, Sorella Carina (Ten Sovereigns), who has raced once, and a yearling filly by Sottsass.