Wikipedia
Magkaisa ( Tagalog for "unite") is a Filipino patriotic song that was composed by Tito Sotto, together with Homer Flores and Ernie dela Peña and sung by Virna Lisa (Virna Lisa Loberiza) who is now based in Virginia, USA. The song's back-up singers were Babsie Molina, Bambi Bonus and Vic Sotto.
It is one of several songs related to the People Power Revolution of 1986, along with Handog ng Pilipino sa Mundo and the patriotic anthem Bayan Ko. The song was greatly popular with the masses in the days after the ouster of President Ferdinand Marcos and his eventual departure to Hawaii on 25 February 1986.
Lisa recorded the song at the Tasha Recording Studio in Libis on the evening of 1 March, 1986. It was then a big hit when the song played on radio stations and the music video associated with it aired on major television stations in the country, a month after the Revolution.
Sarah Geronimo sang the song on August 5, 2009 during the funeral of Cory Aquino. While Regine Velasquez sang her version of the song during the Tatak EDSA 25 concert that commemorates the 25th anniversary of the People Power Revolution.