He was living with his paternal grandparents. Since the census was taken late (16 Aug), it is not clear if Elijah was still living as of the census date or was included because he was alive on 1 Jun 1860, the official enumeration date.
Elijah Aldridge, age 14, born in Virginia, murdered in July.
This has been indexed as both Jul 1859 and Jul 1860. The mortality schedule was supposed to be for the year ending Jun 1860, but since the census was taken in Lawrence in Aug 1860, it looks like deaths up until Aug 1860 were included in the mortality schedule.