Taking baby in arms through security
 

Do I need to get a gate pass for a baby in arms?

Also, this baby is 3 months. Will I need a birth certificate to prove he is under 2? I remember reading that WN tends to require a birth certificate.

Yes, assuming you are traveling with the infant as a lap child, you will need a birth certificate. You will need to check in at the counter, show the birth certificate, and obtain a Boarding Verification Document (BVD). The BVD acts like a boarding pass, and is what you will show at security (if requested) and when boarding the plane.

Put the baby in the diaper bag until you get past the document checker. ;)

I'd leave him in there until you are all the way through tsa. See if the person watching the scanner is actually paying attention.

Shot records that show the baby's birth date also work if you aren't comfortable bringing a birth certificate along. We get them emailed or mailed from the Doctor's office a couple weeks in advance. Our baby's information (name, birth date, height, weight, etc) are on there and that's more than sufficient for the counter agent.

It's also helpful to call Southwest to give them the details of your baby (name, birthdate, etc). This saves some time at the airport counter.

Thanks for the replies.

Leave him in there the whole flight. :D

Seriously though, I doubt WN would require a birth certificate to verify the baby's age if the kid is obviously under two. It should be pretty obvious.

If you don't have the birth certificate, and you encounter the wrong agent, they will make you buy a seat for the child. Angry posts about this pop up all the time on Southwesr's Facebook page, and I believe an incident of this occuring was shown on an episode of the original Southwest-based reality tv show.

The x-rays are harmful, especially to infants.

Checked luggage would be safer.

OP's question is about the checkpoint. The answer is no. BVD's (and a ticket if you are flying WN international) are about WN's internal requirements.

OP asked two questions. ;)

Also, just to clarify, if flying internationally the child (regardless of age) will need a passport, for both Southwest and TSA. TSA may or may not ask for the child's passport at security (depending primarily on whether the gate used is designated for international travel only), but they require all passengers, including children, on international flights have a passport in their possession at all times.

Checked luggage goes through a much stronger x-ray machine than that at the checkpoint!