Si, si, or SI may refer to (all SI unless otherwise stated):

Sarah Asher Tua Geronimo is a Filipino recording artist and actress. Geronimo started her official debut in show business after having won the Star for a Night singing competition. In 2003, after winning the contest, she released her first album entitled Popstar: A Dream Come True under Viva Records. It is considered as Geronimo's most successful album which sold more than 210,000 copies nationwide.

She is the first Filipino artist to receive a platinum award for a DVD copy of her concert The Other Side in 2005 and is currently the only artist who has a platinum record for 4 DVDs of her concert. Her fourth one was awarded with triple platinum status in December of 2010.

Moreover, Geronimo received from the Aliw Awards the "Best Female Major Concert" award for Record Breaker and the "Entertainer of the Year" award, making her the youngest artist to receive it in history.

Geronimo was crowned as the Philippines' Box-Office Queen in 2008 and 2009 for her movies, A Very Special Love and You Changed My Life.

Martina Stoessel is an Argentine actress and singer. She currently has the lead role in the Disney Channel Original Series, Violetta.

Martina Stoessel was born in Argentina, she is the daughter of the director of the Baila Conmigo Paraguay program, Alejandro Stoessel. She has a brother Fran Stoessel. Martina began her artistic training at a young age, performing studied singing, piano, musical comedy, theater and dance.

In 2011, Stoessel was responsible for voicing the Spanish version of the song «The Glow», «Tu Resplandor», which performs the original versión the singer Shannon Saunders. Song is part of the album Disney Princess: Fairy Tale Songs, in which successes are collected from different Disney animated films, as well as the unreleased track.

On March 2, 2012, Walt Disney Records and Disney Channel released the soundtrack of Celebratón, "Celebratón in Concert", a compilation that includes all the hit songs that sounded in the special year-end, which was issued by the screen Disney Channel on December 31, 2011, where Martina performs «Tu Resplandor».

Katherine "Kate" Upton (born June 10, 1992) is an American model and actress known for her appearances in the Sports Illustrated Swimsuit Issue, first in 2011, when she was named Rookie of the Year, and again in 2012, when she was announced as the cover model.

Upton was born in St. Joseph, Michigan and raised in Melbourne, Florida. She attended Holy Trinity Episcopal Academy. Her uncle is U.S. Representative Fred Upton, Republican of Michigan's 6th congressional district.

As a young equestrian, Upton showed at the American Paint Horse Association and competed on a national level. With her horse Roanie Pony, she won three APHA Reserve World Championships – 13 and Under Western Riding, 13 and Under Horsemanship, and 14–18 Western Riding. She was named the 13 and Under Reserve All-Around Champion, giving her a total of four reserve championships (2nd place). In addition, Upton ended up third overall on the APHA youth Top Twenty. With a second horse, Zipped, she won 14–18 Western Riding and was included in the top 5 in 14–18 Horsemanship and 14–18 Western Pleasure in 2009.