A few questions...
Oldbalboy has described the generalities spot on, you'll find most cabin crew very accommodating and airlines very helpful. But there are some specifics. Firstly, where are you travelling from and to and secondly, who are you flying with? Also, will your little one need any food and/or drink? The reason I ask is that if you are flying from the UK, the "Gate Gestapo" ie. security, will attempt to ruin your plans - unless you are prepared for the scum!
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