I can see why someone would think there was Terrier, but I'm not so sure about Basenji. (The only way to know for sure is to do a DNA test.) Both of your dogs look very similar. What breed, or mix, is the older one?
We also have a possible Basenji/Terrier (Yorkie) mix. I've had some doubts, but seeing this picture of Rosie, I can't help but see my Rebel. Such a great looking dog, and if she's anything like our girl, you're in for a treat!
Such pretty pups! Nothing like a tri-baby (times 6!).
I'm sure their eager parents-in-waiting appreciate watching their pup grow… and of course, we're all enjoying it vicariously. :)
Look at the BRAT mixes:
http://basenjirescue.org/DOGS-MIXES/Default.htm
Check out Tia. I think that's what you are looking for. :)
Then look at Tyson and Shiloh. Not the right coloring, but similar build and coat….