If the parent wants the child to receive the blessed ashes, they can be given to the baby. The Old Testament reading for Ash Wednesday includes “children, even nursing infants” (Joel 2:16) in the communal penance. Of course, as a matter of prudence, it is probably wise for the parent to remove the blessed ashes after the liturgy is over to prevent the child from transferring the ashes from forehead to mouth.
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