Hi Amira, the best bit of advice I can give is to try and feed Sarah on take off and landing as this will help to stop her ears from hurting. I flew with my son in October last year (he was 6 months) and this is what I did, my biggest problem was he didn't like sitting still. I found the cabin crew a great help as well, they took my son for a wander whilst I ate and they helped me change his nappy. If you can fly between her sleep times this will also be good. Though if you have a baby who will sleep anywhere then it maybe better to fly at a sleep time. Happy travels.
1 wonderful boy 6 and another on the way