The most common and most likely answer to this crossword clue is the 3 letter word BRO
B
R
O
More clues leading to the result BRO
Buddy explains!

The straight part
We know that "It’s close to Taffy’s heart" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it’s close to taffy’s heart = bro.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 BRO mean?
BRO noun- Brother; a male sibling
- Brother; a male comrade or friend; one who shares one’s ideals.
- Brother; usually used to address a male
- Fratboy or someone that espouses the fraternity bro culture