Sometimes it's fun to be a little too literal.
- The family being pushed repeatedly.
- The reach of a ring.
- Electricity of darkness.
- The gradual destruction of transportation.
- Unable to marry alone.
- Some Masculine leaves.
- Repeating dogs feet.
- Monkey returns to the crib.
These eight all refer to objects that belong in a single set. But one is different from the others and thus there are two distinct subsets (one of which has just one element)... and if you've figured it out, you'll know it, because one of them epitomises the larger subset.
Now, you do need to find the word describing seven of the eight. But that's just leading into the next step. Drop the last letter, and you'll get an anagram of something that belongs to a set of six things, and is the third of that set.
Your task is to identify the number associated with that "third of six" object.
Note - To be clear, only the clues to the eight members of the set are "too literal". I have not hidden "too literal" clues elsewhere in the question.