My 7mth Yorkie refuses to be walked on a leash

Question
She is smart, energetic, and very playful raga muffin named Shelby. However,
when the leash is attached and I say "let's go" and tug on the leash she sits
down and absolutely refuses to walk. My other yorkie and I could stand there
and wait and wait, and she still wont' budge. I have tried the quick tug
method many times, but after awhile she will resort to lying down as an act of
defiance. However, when I let the leash go and I walk away with my other
yorkie, she will sit and wait for a while and then eventually follow us at her
leisure. It's maddening because my other dog and I can't get any normal
walking pace going because I have to constantly stop to look back to see
where she is. it's pretty much a constant stop and go, or a complete no go
unless I let the leash go. Now my other yorkie named Bentley is starting to
follow Shelby's bad habit. Help!

Answer
I wouldn't even try to take her for walks until she knows how to walk on leash. To do so just reinforces bad habits. First thing to do is teach her what to do if the leash accidently gets tight (come forward) and then to learn not to make the leash tight. I clicker train dogs, because it is so much more informative than tugging on a leash (which doesn't really teach and the dog doesn't know what to do about it. When the dog knows what the click means (you are doing a good thing/you'll get something nice for doing that!) I'd let her drag a leash around the house when you are supervising (so she doesn't get caught on anything). Occasionally pick up the leash and put a little pressure on it - while you are making it slightly tight, click - no matter what she is doing. Then present the treat so she comes toward you. Eventually, click when she takes one step towards you, then more. And when she knows that, YOU want to be sure to keep the leash as loose as you can. Imagine you are a 5 lb. dog (or something close) and somebody pulls on you. If you don't want to be pulled off balance, or even off your feet, you may think the smart thing to do is brace backwards. This is what Shelby is doing. If you pull her, she HAS to pull back. So it's your job to keep the leash loose. I'd also consider putting her on a harness instead of a collar, as tension on a collar can damage tiny tracheas. Another thing to consider if she goes muleish on a walk is that she may be tired, and not ready to walk that far. Sandy Case MEd, CPDT