Potty Training for Two

So we have our niece living with us and she had an interest in potty training at one time. Then she was moved to our house and she regressed a bit. So when I tried to potty train her she acted as if I was punishing her. That is when I backed off (completely).
Now Sammi comes to me when she needs her diaper changed (something I would like Khole to recognize and do). So we bought a new potty (we lost the other one in our move) and I have been letting her get used to sitting on it. She has gotten to the point where she comes to me and says, "Potty" while pulling at her diaper. After taking off her pants and diaper I sit her on the potty. I really was beginning to think she was using it as an excuse to get undressed. She very well could be. Then one day I was cleaning up the bathroom after I got the kids in bed. I noticed that there was a little liquid in the bottom. I was so excited. I didn't clean it out so I could show Les. He got home so late that I forgot to show him. Then a couple of days latter she did pee in the potty again and that time Les was home. We were both so excited. Sadly, she hasn't done it again. On the brighter side her enthusiasm hasn't dimmed yet.
Now we come back to Khole. I have been trying to get her to recognize the difference between a clean and dirty diaper. It has been very trying. So just today I decided I needed to take it all into my own hands. It is stressful and keeps me busy. After I changed her into clean clothes and a new diaper I set a timer for an hour. When it went off I took her to the bathroom and sat her on our little potty. I sat with her for about 5 mins trying to encourage her to relax and let it all go. Sammi started crying in another room so I went to her. Five minutes later I got back to Khole. I had decided that 10 minutes was long enough for her to sit on the potty. I asked her if she was ready to get off. She nodded and stood up. I put her diaper back on and looked into the potty. Low and behold there was pee in it. I showed her how happy it made me (get her more incentive to do it more). I repeated this every hour for 10 minutes. She did it one more time before I had to go pick up Les and get some shopping done. I set the timer on my phone so that while we were out I could take her to the bathroom in the store. She did go one more time while we were out. She has been in the same diaper all day because it has been DRY! I think we are well on our way but time will only tell.
Khole was actually on the potty as I was writting this. When the timer went off I went to get her. She had once again went pee in the potty! Oh I learned one other thing today. I either intimidate or make her too nervous. She is so tense while I am in there. The first time she went it was while I was gone. So now I leave her to sit in private. She does much better that way. Of couse, I don't expect results everytime she I put her on the potty since I have observed that she has only gone 4 times today. After she gets used to the routine I will lenghten out the time in between visits.
Eventually I will do the same for Sammi. Right now she is showing me when she is ready. One day after Khole has settled into a routine I will take more control and get her on a schedule too.
Wish us luck as we all embark on this new journey. Emma kept regressing everytime I thought I had her potty trained. One was stressful. Now I am doing two. I must be crazy.