The bible says plenty.
Old testatment
Exodus 22:22-24 "You shall not afflict any widow or fatherless child. If you afflict then in any way, and they cry at all to Me, I will surely hear their cry; and My wrath will become hot, and I will kill you with the sword; your wives shall be widows, and your children fatherless."
Psalm 82:3
"Defend the cause of the weak and fatherless; maintain the rights of the poor and oppressed."
Deuteronomy 14:28-29
"At the end of every three years, bring all the tithes of that year's produce and store it in your towns, so that the Levites (who have no allotment or inheritance of their own) and the aliens, the fatherless and the widows who live in your towns may come and eat and be satisfied, and so that the LORD your God may bless you in all the work of your hands."
New testament
Acts 20:35
"In everything I did, I showed you that by this kind of hard work we must help the weak, remembering the words the Lord Jesus himself said: 'It is more blessed to give than to receive.' "
Prehaps some of things said by Jesus were more powerful
Matthew 25:36-38
36 I needed clothes and you clothed me, I was sick and you looked after me, I was in prison and you came to visit me.’
37 “Then the righteous will answer him, ‘Lord, when did we see you hungry and feed you, or thirsty and give you something to drink? 38 When did we see you a stranger and invite you in, or needing clothes and clothe you?
Or prehaps the most important verses in the bible which appears in all four gospels.
Mark 12
"28One of the teachers of the law came and heard them debating. Noticing that Jesus had given them a good answer, he asked him, “Of all the commandments, which is the most important?”
29“The most important one,” answered Jesus, “is this: ‘Hear, O Israel: The Lord our God, the Lord is one.e 30Love the Lord your God with all your heart and with all your soul and with all your mind and with all your strength.’f 31The second is this: ‘Love your neighbor as yourself.’g There is no commandment greater than these.”
Canon law does not pretend to superceed the gospels. Catholics are commanded to love LAC kids as they are our neighbours. The catholic church may require parents to seek a catholic school, but they will not damn a child who is unable to attend a catholic school. There are plenty of catholics who attend secular schools all over the world.
I wonder what Pope Francis' opinon would be on not giving priority to LAC children in catholic schools. (unlike the rest of UK state schools)