I am not bringing anything for her since she is 2 and we got her a seat of her own. For your ds you should bring a copy of his birth certificate if he is going to be on your lap just in case they think he looks over 2, which is doubtfull.
We have traveled with Isabella alot and I have never been asked to show anything for her, but I always brought it just in case.
Your dd has her own seat, doesn't she?
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