Series Resonance in Crystal
Add 47pF capacitors from both ends of the Crystal to GND. You now have a PI filter. Make Rload 100Kohm, to have minimal effect on the crystal behavior.
Make Rsource variable, from 10 ohms to 1Kohm.

Now perform analyses. Or run sims, with tiny time steps. And inject a single edge into bottom of the left-most 47pF cap, to kickstart the oscillation