Olive or warm green. You can get a color that's a bit more green than the current color.

Cottage style with warm muted sage-green

Herb Bouquet appears to be close to the color on the home below:

Nothing "stays" forever. Maybe your parents don't want to think about an overall plan. You didn't say anything about the windows. How old are they?

The greens are great! And I really like the super-wide window trims; maybe paint the trim just a smidge off-white so it’s not so stark against a muted green. A deep green front door as in celery’s sample above.

The home is lovely. A classic design.

With brick, roof, and gutters all staying, it's really hard to judge from paint chips alone - everything interacts. The warm tones in the brick will shift how any green reads on the body.

A couple tools that helped me in a similar situation: the Sherwin-Williams ColorSnap Visualizer lets you test their colors on a photo, and fassia.io works with any color freely (not locked to one brand). Full disclosure I built fassia.io, but both are free so worth trying before committing to test pots.