Capsaicin is oil/fat-soluble so try washing your hands with a little whole milk, or rub with sour cream or vegetable oil and see if that helps.
Just as you can get it in your eyes if you rub them with your fingers, I'm sure you can easily transfer it to your baby.
I'm just surmising here, not speaking from experience so if you try any of these, be sure to let us know how they worked....or what you did instead.
Many references indicate that stress on the plant effects the heat rating of the fruits produced. "Good" stress (usually people want to increase heat) is generally a reduction in water supply, carefully and aptly timed, and/or increased outdoor temperatures.
While appearing dated and non-authoritative, this site, also looks very accurate from my experience around growing chiles, and states that (as is common, referring to spice/heat as pungency):
...total pungency amount of the medium and mild chiles increase
dramatically when put under stress.
Normally, chile plants like summer weather (sunlight and warmth), and are not nearly productive in winter. What you're obtaining in winter months may be imported from a very different location, probably from a place on Earth where it was summer when harvested. As indicated in the above-cited article, the truly hot peppers don't get much hotter from stress.
Anecdotal addendum: fwiw & ime, chile plants grown in winter (the ones observed are nagas, tabasco, japone, jalapeƱos) aren't as productive and the peppers are not anywhere near as hot. So, when not grown in the proper conditions that a species expects - mostly enough daily sunlight or a long enough warm season, the heat in produced fruits can drop dramatically.
Best Answer
The heat in peppers (capsaicin) is quite stable. Any number of preservation options will work, as long as you include the hottest part of the peppers which are the ribs and membranes holding the seeds.
You can choose a method based on your goals and ambition:
For your use case (storage for a few months prior to making hot sauce), freezing may be your best option.
See also: