Quote:However, you may purchase male or female slaves from among the foreigners who live among you. You may also purchase the children of such resident foreigners, including those who have been born in your land. You may treat them as your property, passing them on to your children as a permanent inheritance. You may treat your slaves like this, but the people of Israel, your relatives, must never be treated this way. (Leviticus 25:44-46
Children of foreigners could be kept as a permanent inheritance so the Jubilee laws didn't apply to them.
I admit, the Jubilee has always fascinated me because it seems like a great opportunity for people to start fresh from debt and slavery; however, it appears to have only applied to Hebrews. Even foreigners who had been born in Israel could be kept as permanent slaves.