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Smooth curve in the Hilbert flag scheme

Let $d$ be an integer greater than $0$. Let $P_2$ be the Hilbert polynomial of a degree $d$ surface in $\mathbb{P}^3$. Recall, the Hilbert flag scheme $\mathrm{Hilb}_{P_1,P_2}$ parametrizes curves $C$ contained in a degree $d$ surface $X$ in $\mathbb{P}^3$ such that $P_1$ is the Hilbert polynomial of $C$.

Now consider the first projection map from the above Hilbert flag scheme to the Hilbert scheme of curves with Hilbert polynomial $P_1$, denoted $\mathrm{Hilb}_{P_1}$. If we look at the image when can we say that there exists at least one smooth curve in every irreducible component of the image?