We flew out of our home state of NH and flew to Florida for vacation. I took all the steps to make sure my son and family were safe on the flight. I called Southwest when booking the tickets and we spoke about my son’s allergies. They told me that they could not prevent him from coming in contact with residue 100% but would try and make sure he was safe on the plane. They gave me instructions to follow from the time I arrived at the airport to the time we landed in Florida. The ticket counter attendant checking our bags told me there was a note on our reservations that said my son had a severe nut allergy. I told them yes that was the case. she made a special mark on our boarding passes that signaled the crew and gate attendant. She then told me to make sure we lined up for boarding before everyone else with those in need of assistance to board. When we entered the plane, I spoke with the flight attendant and she reassured my wife and I they would not be serving nuts on the flight. We were able to pick the seats we wanted to sit in and they helped us clean the seats and all surrounding surfaces with the Clorox wipes we had brought. As the plane was getting ready to take off they announced over the loud speaker that there was a child on the plane with severe peanut and tree nut allergies and they would not be serving snacks with nuts in them and that if everyone could possibly refrain from eating any nuts on the plane for the duration of the flight.