According to the Catechism of the Catholic Church, from its beginning until death, human life is surrounded by their watchful care and intercession. "Beside each believer stands an angel as protector and shepherd leading him to life." Already here on earth the Christian life shares by faith in the blessed company of angels and men united in God (CCC, n. 336).
In the Gospel of Matthew, Jesus says that there are guardian angels for individuals, including for little children. “See that you do not despise one of these little ones; for I tell you that in heaven their angels always behold the face of my Father who is in heaven” (Matt. 18:10).
Angele Dei Prayer (English Translation)
Angel of God,
my guardian dear,
to whom God's love
commits me here,
ever this day,
be at my side,
to light and guard,
rule and guide.
Amen.