Is overnight travel better or daytime travel better for a 14-mon

I have to take my 14-month-old daughter to London next week. I don't know if I should book overnight tickets, or fly during the day. Please help!

Overnight flight:
pro: less stress for parents, baby will want to sleep the whole time, not much eating and pooping and it is also easy to deal with the in-and-out of the airport.
con: baby's night time sleep will be disturbed many times, if not able to sleep comfortably, baby will cry a lot.

Daytime flight:
pro: baby's sleep will not be disturbed at all, should be in a pretty good mood and less crying.
con: easily get bored and may fuss, lots of daily routine to follow, and she might want to walk around...

Here is my daughter's 1st birthday pictures as a thank you for answering my questions. Many thanks.

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