You can find the interests of only some of the members of the royal family but for the brothers and sisters of the grand duke, I think it's harder. I only found informations about their education, weddings and children.
The first picture is Sibilla's father, Paul Weiller, with Josephine-Charlotte. I believe this picture was taken shortly before he passed away.
The second picture is Sibilla's mother, Donna Olimpia Torloni di Civitella-Cesi, on the left in the black suit. The elderly lady in the middle with the coat on is Sibilla's grandmother [her mother's mother], Infanta Beatriz of Spain [her parents were King Alfonso XIII and Queen Victoria Eugenie (Ena) of Spain, so Sibilla is a great-granddaughter of Alfonso and Ena].
Both of these photos were taken at Prince Paul-Louis' baptism in 1998.
[COLOR="Purple"]What is a wedding? Webster's Dictionary defines a wedding as "The process of removing weeds from one's garden."
--Homer Simpson, giving a lecture on marriage