It sounds to me like a guitar phrase (after all, her husband is the guitarist, and a really good one). That being said, it could be a general clean guitar thing.
you mean the pitch-bendy phrase bending up to the third?
Sounds to me like a synth rather than a guitar (although played guitar-like).
I suspect a DX7 (good guess for anything “non-subtractive” in the 80s). But I guess you could also get close with a virtual analog, using a high-passed pulse-width-modulation sound (start with a narrow pulse to begin with and modulate PW to liven it up; maybe add some chorus). But the somewhat “nasal” quality reminds me a lot of some of my DX7 leads from days gone by…
It does sound kind of like that as well to me. Definitely not a real guitar.
Using the Arturia DX I worked through a bunch of the (Yamaha) factory patches and I think I found something really close. I seem to remember a patch called “Lead B” on the original cartridge, but Arturia doesn’t name the factory sounds (they refer to them by their cartridge and position), and my DX7 has long been in the attic, in need of a battery replacement
I checked through the factory ROM banks using Dexed (very nice free DX emulation). There’s no “Lead B” in the factory, but the SYN-LEAD 5 comes pretty close to the recording - with a bit of effects and EQ, you could fake this well enough for live…
That patch is also available on the Arturia: Rom2B 04 SYN-LEAD 5 (my version of the Arturia DX does name its patches…)