This is a generalization of my previous question: What are all finite groups such that all isomorphic subgroups are identical?
Specifically, what finite groups $G$ have the following property: For any two subgroups $1 < H, H' < G$ that are isomorphic, then $H \cap H'$ is non-trivial.
Some quick results: This property is equivalent to all prime order cyclic subgroups being unique. Also, each of these subgroups are normal.
If $G$ is an abelian group, it turns out $G$ is cyclic. (Proof: $G=G_1 \times \cdots \times G_n$, each cyclic, with $|G_i|$ dividing $|G_{i+1}|$. Two factors share a common prime $p$, hence two disjoint copies of $C_p$, so no two factors exist.)
However, there are non-abelian groups that satisfies this condition (if I've thought through it right). Take the Quaternion group, which from the subgroup lattice is easily seen to have the desired property.
Can the (non-abelian) groups with this property be easily characterized?