Absolutely!
According to Southwest's site: "Customers traveling with children will be allowed to check one stroller and one Child Restraint System (CRS) or car seat per child without charge. This is in addition to the regular free baggage allowance."
Find out more about travelling with baby here. Be sure that if you are travelling with your baby as a lap child that you bring a copy of the birth certificate.
Let us know what other questions you have, and check out the Community Knowledge Base for more as well.
-A List, Companion Pass holder
