After reviewing the visitation rules for all the Dallas County facilities in Lew Sterrett, the terms are not clear for a car seat. They do however prohibit child strollers and toys.
https://www.inmateaid.com/ask-the-inmate/i-want-to-bring-my-baby-to-go-see-his-dad-on-saturday-at-lew-sterrett-in-dallas-county-are-you-allowed-to-bring-a-car-seat-in-to-the-jail#answer
Accepted Answer Date Created: April 13,2013