Can two related "spends" be in the same block? Consider the case where:

Address A has some BTC.
Address B is empty/zero.
Address C is the intended recipient.

B sending to C is invalid on its own, but does make sense if associated with A sending to B first
Can two dependent transactions be put into the same block and accepted?

A ==&gt; B
B ==&gt; C


(Since the net result will be OK, even though the second transaction does not make sense until the first one is completed)
Yes, but only if A -&gt; B is placed before B -&gt; C in the list of transactions.
Here is a graph of the percentage of transactions spending each other in the same block, it is usually around 10%.