Mirabilia Dei Children's Choir (MDCC) also known as Betis Children's Choir are composed of young boys and girls came from different baranggays of Betis since 2001. They are having their regular rehearsal every Sunday morning at Mendoza's Residence in San Agustin under the guidance of Msgr. Greg L. Canlas (Music Director of Mirabilia Dei Foundation, Inc. and Principal Conductor of MDCC) since 2006. 

As they continuously trained and developed their singing skills, the group was asked and requested several times to serve and sing not only in their parish but also in different Archdiocesan celebrations like the 50th anniversary of the Coronation of Virgen Delos Remedios in Villa Del Sol, Chrism Mass and anniversary celebrations of the Archbishop Emeritus of San Fernando, Pampanga, Most Rev. Paciano B. Aniceto, D.D. They also sang during the ordination of the other two Kapampangan bishops, Most Rev. Pablo Virgilio S. David, D.D. Aside from various parish and archdiocesan celebrations where they were invited to sing, the MDCC also hold their annual concerts in different venues in Betis, Bacolor, San Fernando and Angeles CIty. They also had the opportunity to have a joint concert with the UP Cherubim and Seraphim Children's Choir which was held in Betis Church in 2007 conducted by Msgr. Canlas and Dra. Mirano of UP College of Music. They were also invited to have a joint concert with Las Piñas Boys' Choir held in St. Joseph Parish Church in Las Piñas City under Mirabilia's first Music graduate, Mr. Paul John G. Layug back in 2016.

At present, the group regularly serves the anticipated mass at St. James Parish Church in Betis every Saturday, 5pm and other barrios in Betis while preparing for their annual concert at the same time.