V.T.
I just did a transatlantic flight with a 16 month old with the bassinet. The bassinet saved us. Even though she didn't sleep much, she had her own space in the bassinet and loved playing in it. She did sleep over 1 hour in it, but the flight was in the middle of the day, so she would of been awake anyway. I would think with a 4 month old she will still sleep most of the flight. Do you need the car seat overseas? We didn't use a car seat when we went to Austria, so we were able to take a nice umbrella stroller with us. If you do need the car seat, you can take it through security with you and gate check it, but I would just check it at the ticket counter so you don't have to lug it around, and check your stroller at the gate. You may want to buy a snap and go for the infant seat. They are around $70 and pretty light weight. Also, we travelled a lot with our daughter when she was young, and our pediatrician said to not worry about feeding too much. She told us to give our daughter as much milk as she wanted and to cluster feed if we needed to to keep her calm. Don't forget to feed on take off and landing to help with the ear popping. Usually we put the stroller and car seat through the conveyer belt, but when it didn't fit through they pulled it aside and scanned it separate. It took an extra 5 minutes, no big deal.