According to Ancestry.com, the 1860 Springfield, Illinois US Census shows that living in the household of Abraham Lincoln was his wife Mary, sons Robert, Willie, and Thomas and two "servants".

What was the status of those two servants?

Mary Todd Lincoln's family were slave owners. While Illinois was a "free" State, with the Dred Scott decision Mary could have owned Slaves outside her native State of Kentucky because that ownership was legal were she was born.

Were these "servants" slaves given to her by her father? Or were they actually emancipated? Since A womens property was actually the property of her Husband in 1860, did Lincoln in fact own them?