about one pixel ($2 \cdot \pi$ with parallax $\pi$). We could not find evidence for variability of the GQ Lup companion in the K$_{\rm s}$-band (standard deviation being $\pm 0.08$ mag), which may be due to large error bars. No additional companions are found with deep imaging. ]{} [ There is now exceedingly high significance for common proper motion of GQ Lup A and its companion. In addition, we see for the first time an indication for orbital motion ($\sim 2$ to 3 mas/yr decrease in separation, but no significant change in the position angle), consistent with a near edge-on or highly eccentric orbit. We measured the parallax for GQ Lup A to be $\pi = 6.4 \pm 1.9$ mas (i.e. $156 \pm 50$ pc) and for the GQ Lup companion to be $7.2 \pm 2.1$ mas (i.e. $139 \pm 45$ pc), both consistent with being in the Lupus I cloud and bound to each other. ]{}

Introduction: GQ Lup A and its companion
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Based on three epochs of imaging data spanning five years, Neuhäuser et al. (2005, henceforth N05) presented evidence that the $\le $ few Myr young T Tauri star GQ Lup has a co-moving companion with 