Just need to see what the majority would do...
I am booked to babysit for my friend so that she can go to her works Christmas do in December.
Havent told dh as forgot about it.
Came in from work last night and he tells me with a big grin that he has booked a little weekend away in our new caravan....on the weekend of my friends do.
Freind suggested yesterday that i have her baby overnight instead of going to her house...i felt a bit pressured so said, ok.
Now dont know who to let down 
btw friend has no family at all near by to babysit for her, i do all of her babysitting. she has bought tickets for her & her dh already.