Broody off he nest

How long can a broody bird stay off the nest? I have a female turkey that went broody at the end of last week and is sat on 10 eggs. i know she will need to come off the nest to eat and drink etc but how long do they come off for because she came off today while i was there and she was off them for almost two hours! im not sure if she stayed off longer because i was there and she wanted some treats or if it is normal to come off for this long.

i know its not that, i check for mites regular and touch wood have not seen any! i personally think that it was because i was there and she is the only very tame one and follows me around to get treats! i actually went out of the way so i couldnt be seen by her then she went back to sit on the nest again, but this is the only day i have actually seen her come off the nest since she went broody.