Does the rule to maintain family ties apply to Slaves?

Quick question about Slavery in the shariah law when slavery was active. From what I understand, Islam discourages one to cut of family members, maintaining family ties are very important. What about a person who has been enslaved after war, after the remainder of a tribe/nation has been enslaved. According to Shariah when slavery was active, did the owner have to allow the slave to maintain their original family connections with the ones alive, e.g. a mother with her child who had passed puberty or ones grandparents etc, or was this an exception? Thanks