YorkieTalkJilly gave you some excellent advice, please follow it. Your little girl is 4 months old and trust me it can take some time training a Yorkie.
As for walking on a leash, get a harness and a short leash and start slow. Sparta is looking at you as her Mother now, Mother's teach.
Please, please, please put the rolled up magazine down (or anything else you may be using). Your Sparta is a baby, she is very fragile, treat her that way.
Be consistent with training and make sure you make time to spend loving and cuddling also.
__________________ Cheryl,Mom to SophieKate |