What determines when order is given?
Spanish orders are given out by royal decree, which has to be countersigned by the King and one or more ministers in the Spanish government.
As an example, see below the
royal decree conferring the collar of the Order of the Golden Fleece on Queen Elizabeth II of the United Kingdom. It is signed by King Juan Carlos and then Spanish prime minister, Felipe Gonzalez.
REAL DECRETO 441/1989, de 5 de mayo, por el que se
concede el Collar de la Insigne Orden del Toisón de Oro a
su Majestad la Reina Isabel II del Reino Unido de Gran
Bretaña e Irlanda del Norte.
Queriendo dar un relevante testimonio de Mi Real aprecio a Su
Majestad la Reina Isabel del Reino Unido de Gran Bretaña e Irlanda
del Norte, y en muestra de la tradicional amistad entre el Reino Unido
de Gran Bretaña e Irlanda del Norte y España;
Oído el Consejo de Ministros,
Vengo a concederle el Collar de la Insigne Orden del Toisón de Oro.
Dado en el Palacio de la Zarzuela a 5 de mayo de 1989.
JUAN CARLOS R.
El Presidente del Gobierno,
FELIPE GONZALEZ MARQUEZ
On your second question:
Does Infanta Sofia already have it? I have seen Swedish royal babies wearing orders at their baptism . Just curious
As far as I know, Infanta Sofia doesn't have any order yet. As she grows older, she will probably get the Grand Cross of the "Royal and Distinguished Spanish Order of Carlos III", which is the same order that her mother, her aunts and her grandmother have. The Order of the Golden Fleece is normally reserved to the heir to the throne only.
In Sweden, orders are also given out by the King, but under regulations introduced by the Swedish government in 1974, orders could be bestowed only upon foreign nationals; however, those regulations were later amended to allow the King to give orders to members of the Royal Family in addition to foreign nationals or stateless persons. Traditionally, the Royal Order of the Seraphim was presented to princes of Sweden at their baptism, but they didn't actually start wearing it until they came of age. In the case of King Carl Gustaf's children specifically, they received their orders
retroactively when they turned 18 as they couldn't get it when they were born under the unamended 1974 regulations. The regulations were actually amended in 1995, precisely the year when CP Victoria turned 18. The King's grandchildren (both male and female) got their orders at their christening ceremony, but again they won't wear it until they are 18.