The most common and most likely answer to this crossword clue is the 11 letter word DESCENDANTS
I've seen this crossword clue in The Daily Telegraph
D
E
S
C
E
N
D
A
N
T
S
More clues leading to the result DESCENDANTS
- Who form lines and swoop down on insects
- They extend a line — casts twice end badly
- More than one follower in family and sect ends badly
- . Passes away. His heart wasn't there. Cold extermination by workers and successors
- Children at last have medieval music around on Sunday
- Family take a dip, busy creatures
- Offspring drawn regularly into paths leading downwards
- Come down on workers and their offspring?
Buddy explains!

The straight part
We know that "Family" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case family = descendants.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DESCENDANTS mean?
DESCENDANTS noun- One who is the progeny of a specified person, at any distance of time or through any number of generations.
- A thing that derives directly from a given precursor or source.
- A later evolutionary type.
- A language that is descended from another.
- A word or form in one language that is descended from a counterpart in an ancestor language.