Do you think it's important for a Filipino couple to get married even though they have been living together for many years now and have three children?

Yes. Marraige is important not only for sacred reasons but also legal reasons. Kung gusto mong iyong iyo ang asawa mo, malaki ang karapatan mo at ng mga anak mo sa buhay ng asawa mo, magpakasal kayo. Kahit west wedding lang sa municipyo niyo. This is important kasi it's to secure what you have and what your children have and deserve. Make it official and LEGAL.