Unless you have some physical disability factoring in a flexibility or reach impediment, e.g. healed broken finger or painful arthritis, you'll cross that 'stream' soon enough to look back and self-deprecatingly chuckle to yourself at why you even considered a 'puddle' an obstacle at all.
With your reference, you'll have to be more specific. Is it fingering a particular chord formation requiring the fretting of the 6th string at the third fret, i.e. Open G, as taught by Lisa in her lesson?
Or....?
If it's G and you're forming it with fingers 2, 3 & 4 as inferred by your reference to your "little pinkies", (plural ??), then IME it will feel more awkward because we are more used to and naturally inclined generally to use our stronger fore, index and ring fingers rather than the little finger alias 'pinky' for tasks generally, including forming many of those initial open chord formations.
If you've played previously using the more common (IME) conventional open G fingering and subliminal memory has retained some recall that motor skill to be unlearned, that feeling of awkwardness can be accenuated.
Regardless, IME it just takes time and (repeated) application to build up strength and dexterity in the little finger, but we notice it more initially when learning to play guitar because we're challenged with overcoming in mind and body, its pre-conditioning to its normal role as the lazy or idle finger in daily tasks otherwise.
Watch the lesson, presumably Lisa's, a few times if necessary paying particular attention to chord formation detail, suggested finger and thumb placement, laydown sequence and timing sounding the target strings individually and alternatively collectively to ensure you are sounding them cleanly. Hasten as slowly as necessary.
In other words, don't be impatient with yourself. It'll take as long as it takes. Keep at it, with breaks to avoid frustration of reinforcing failure when your attention wanes. Once you are sure you understand the technique, persist with time and repetition to the objective and you will discover accomplishment the reward. If tending to wordy or verbose rather than a characteristic texted platitudinal one liner rexponse, I'm not articulating hypothetically here, but from my personal experience.
Old age - you weren't specific (< 50 isn't "old" as applicable to markedly impinging on learning, again IME), will as a rule present encumberances to general dexterity and rate of acquiring motor skills, but should also come with significant advantages. i.e. patience, discipline, determination and wisdom all of which affect all important application and understanding. Derived comparing then and now. FTR I can play both as in either or at will, open G fingerings instinctively, changing seamlessly and alternatively now acoustic or electric (& which fingerboard/neck) regardless. I'm older (60s) btw, been with GT since Feb 18, kicked off in Nov 17. So if I can, you can too. As you can see, it doesn't take long.
A personal observation I don't ignore. Hand size or more accurately finger length can be advantageous, or not. I certainly wish I had spider fingers. But I don't. But that said, I just get on with it with smaller hands and fingers and I manage. But I'll never have an easy five fret reach. I find inspiration of what is achievable from admirably accomplished players like Jack Thammarat who doesn't have the large hands, finger length or flexibility of ectomorphs like Malmsteen, Vai -with an extra digit too, Berry, Atkins, or Hendrix all do/did RIP. Most everyone not so gifted does find stretching difficult initially, especially using muscles in fingers that previously haven't had to do much more than just be. IMPE, a correctly sized neck and fingerboard fit is more critical for smaller hands. That said, Yamaha's F310 is beginner orientated with a shorter scale, narrow string spacing and medium nut, so it's an easy player for smaller to average (medium) sized hands like my APX600 is.
In closing, equally applicable to your request and current specific difficulty, in my journey thus far, IMPE tenacity is the singular most important skill to master in effectively learning guitar. With it, you'll get there. Remember to enjoy the journey, all of it, including the obstacles. Cheers.
