Wither Bone
Have you ever wondered why withers don’t drop any items? In vanilla Minecraft, this feature is absent, but with the mod titled Wither Bone, you will be able to collect their bones. After defeating withers, you will receive their bones, which can later be crafted into bone blocks.
To ensure the mod functions properly, make sure to enable experimental gameplay. 
First, as obvious as it may sound, you need to defeat a wither. After that, place the wither bones on the crafting table to create a bone block. 
If you are playing in creative mode in Minecraft, you can use the following commands:
- /give @p wb:wither_bone
- /give @p wb:wither_bone_meal
- /give @p wb:wither_bone_block
Installing Wither Bone (.mcpack)
- Download the mod labeled as “.mcpack” below.
- Open the downloaded file to import the add-on/texture into Minecraft.
- Launch Minecraft Pocket Edition and navigate to the world settings.
- For your world, enable the imported:
— Resource Packs.
— Add-on Packs. - Select the imported resource packs/add-ons in each section.
- It is recommended to restart the game client of Minecraft PE afterwards.
- Start Minecraft Pocket Edition, enter the previously configured world Minecraft, and enjoy the add-on!