By Basu's theorem, we know that any ancillary statistic is independent of a statistic that is both sufficient and complete. I was wondering if the assumption of sufficiency and completeness can be relaxed.
If $T$ is a complete statistic for a family of distributions $\mathcal P = \{ P_{\theta} , \theta \in \Theta \}$, then for any ancillary statistic $S$, can we show that $S $ and $T$ are uncorrelated?