K.C.
You should go on the trip - it is important for you and your husband to connect with each other and get a break from parenting for a few days. It is not too long to leave your son, especially if he is with people he knows and loves (like grandparents). He will not be traumatized.
As for nursing, I can't say how he'll react when you come home. But if you pump while you're gone, you'll be able to keep your supply up and continue nursing upon return if he still wants to.
As for his intake, he's old enough that breast milk isn't really providing his main nutrition anymore (I assume he's eating a lot of table food by now), so having less for a few days won't hurt him physically. He can drink more water to make sure he's still getting enough liquids each day if he doesn't want the milk in bottles.
Also, if the trip isn't for a few months, things may change between now and then. Work a little harder (without adversely affecting nursing) on getting him to take a bit more from the bottle so he's used to it when the trip comes along.
K.
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