  For a non-negative integer $\ell$, the $\ell$-leaf power of a tree $T$ is a
simple graph $G$ on the leaves of $T$ such that two vertices are adjacent in
$G$ if and only if their distance in $T$ is at most $\ell$. We provide a
polynomial kernel for the problem of deciding whether we can delete at most $k$
vertices to make an input graph a $3$-leaf power of some tree. More
specifically, we present a polynomial-time algorithm for an input instance
$(G,k)$ for the problem to output an equivalent instance $(G',k')$ such that
$k'\leq k$ and $G'$ has at most $O(k^{14})$ vertices.
