Bucket Glitch

So today, I decided to play Minecraft. I took a bucket and got some water in it. The bucket then disappeared from my hotbar. I searched in my inventory and found it. i clicked on it and placed some water. The bucket again disappeared from my hotbar. I checked my inventory and there was my empty bucket, in a different place. Not only that, one of my brothers were able to stack his water buckets (not sure if that's a glitch), and for my other brother, he placed the water down and it was gone from his hotbar and his inventory. Please fix this Mojang!!!