Maybe my question is stupid, but, why you need to rehash each block after changed block after changing data in blockchain?

Block contains a hash of its data and hash of previous block. If i change the data in block № 9000, than block № 9001 will refer to a nonexistent block. Сhain will be broken. Every article that i read says something like:

To make this work, you will need to rebuild and rehash each block following the tampered block, replacing the contents of the previous-block-hash pointers.

But, if block contains only hash of previous block, why i cant just change the previous block hash value in block № 9001 if i change data in block № 9000? This should restore the chain?