I will give 3 proofs for showing,
There exists a family of subsets \mathfrak{F}, of \{ \cdots n\},
* such that each element A \in \mathfrak{F} is of size \frac{n}{4}
* for any pair A,B \in \mathfrak{F},\ |A \cap B| \leq \frac{n}{8},
* and |\mathfrak{F}| = 2^{\Omega(n)}