Counting preservation in West Virginia

While it would be nice if fortune went more hand-in-hand with fame, fame sometimes brings one a nice surprise. I often get inquiries from people looking into languages and writing systems, and sometimes those queries are really very interesting. Last night, I received a very nice request from a charming person from West Virginia whose initials are V.E.L., who was born in 1927ː

Good evening to you, sir. This may sound very stupid to you but I'm willing to take that chance to ask you a question; I'm 80 years old and, as a young kid, I remember my Mother telling me and my siblings that she could count to 20 in Cherokee. We, of course, memorized that stuff and still have most of it stored in the old noggin. It went like this; teen, tain, tether, fether, fimps, matha, latha, catha, doublo, beaudix, teendix, taindix, tetherdix, fetherdix, bumpus, teenbump, tainbump, tetherbump, fetherbump, jenkus. (1 to 20)

It turns out that the numbers one to ten in Cherokee really don't have anything to do with the list which V.E.L. gave.

1	sa'wu
2	ta'li'
3	tsoː'i'
4	nvgi'
5	hiːsgi'
6	su'dali'
7	galoquoː'gi'
8	tsuneːla'
9	so'neːla'
10	sgo'hi'

So it's not Cherokee.

Is there any possibility that there was any merit at all in this, or was she simply kidding with us? I have been under the impression that dix was possibly French for 10 and that, coupled with teen for 11, makes a little bit of sense to me. The spelling is just my idea of how the words sounded and I am not a linguist at all. If you can find time to respond, it will greatly appreciated.

I think there's a good chance it's Welsh. At least some of it is. It's five and the shift after fifteen that clinch it for me.

№	W.Va.	IPA	Welsh	IPA
1	teen	tiːn	un	iːn
2	tain	tɑɪn	dau	dɑɪ
3	tether	ˈtɛðər	tri	triː
4	fether	ˈfɛðər	pedwar	ˈpɛdwɑr
5	fimps	fɪmps	pemp	pɛmp
6	matha	ˈmɑθə	chwech	xwɛx
7	latha	ˈlɑθə	saith	sɑɪθ
8	catha	ˈkɑθə	wyth	wɪθ
9	doublo	ˈduːblo	naw	nɑʊ
10	beaudix	ˈboːdɪks	deg	deg
11	teendix	ˈtiːndɪks	un ar ddeg	iːn ɑr ðeg
12	taindix	ˈtɑɪndɪks	deuddeg	deɪðeg
13	tetherdix	ˈtɛðərdɪks	tri ar ddeg	triː ɑr ðeg
14	fetherdix	ˈfɛðərdɪks	pedwar ar ddeg	ˈpɛdwɑr ɑr ðeg
15	bumpus	ˈbʌmpəs	pymtheg	ˈpɪmθeg
16	teenbump	ˈtiːnbʌmp	un ar bymtheg	iːn ɑr ˈbɪmθeg
17	tainbump	ˈtɑɪnbʌmp	dau ar bymtheg	dɑɪ ɑr ˈbɪmθeg
18	tetherbump	ˈtɛðərbʌmp	deunaw	ˈdeɪnɑʊ
19	fetherbump	ˈfɛðərbʌmp	pedwar ar bymtheg	ˈpɛdwɑr ɑr ˈbɪmθeg
20	jenkus	ˈdʒɛŋkəs	ugain	ˈigɑɪn