Aside from ear popping issues, the best advice I can give you is options for the child. At 6 months, the best gift I received from a FA was a stack of plastic drink cups (about 6 - one for every 30 minutes on that flight). The crinkle sound when my son played with the cup was total entertainment for him. We'd replace it if it he cracked the cup or dropped it on the floor and was putting it in his mouth. The 1 per 30 minute rule worked quite well. At 12 months, it's a whole different issue. The best gift from a FA at that stage was her volunteering to take him on tour of the entire plane with her (he was walking well by then). The best 30 minutes of my life I must add (it was a JFK-NRT route on AA). I miss her dearly.