Phyllis, have you tried using puppy training pads with Leo? Try putting them where he has a bowel movement. They have an attractant on them that makes dogs want to go potty on them. You can get them at Walmart.
Also, you might try showing him where he went and telling him no, then picking it up and taking it and him outside and put it in the grass for him to see. This might take several tries before he actually gets the connection. When he finally does go outside, give him a treat

for it. Some pekes are more stubborn about potty training tha others.
I have an older guy who doesn't want to go potty outside when it is raining out either. I have found that if I just make him stay out long enough he will finally go. Hope this helps some. Leo is pretty young yet, so its just going to take some time and extra patience on your part with him.