Extra Prayer?

The method by which I'm training my kids to pray is what I call the assimilation method. When S turned 7, I gave her a choice to choose between two prayers. This method was introduced to me by a fellow homeschooler, who I have very high respect for. She chose Maghrib. The reason why I went for this method is because it introduces the training of prayer to a child in a non intimidating way. By being given a choice, the child hopefully won't feel pressured into doing it, and will feel that she has control. When I was trained to pray, I had to do all five and after a while, it felt like a chore. I won't go through what I did back when I was 'in training' for that includes many things I don't want my kids to do.

Ss S chose Maghrib. The deal was that she would only pray one prayer out of the whole five, but she has to do it every day, without fail. It's a commitment. I told her this and she agreed. I tried to make a big deal out of the whole thing too, by making her her own prayer garment from a fabric she chose herself. We also made her feel like she had attained a special level by joining us in the worship of Allah on a constant basis.

After about six months or so, I asked her if she was ready to add another prayer. She said she was and we added Asr. Now she's eight and we just recently added Fajr, upon her insistence. I had given her the other prayers as choices but she insisted on Fajr. Somehow, this child of mine is fascinated by the idea of waking up early in the morning and staying up, never to go to sleep again until it is time for bed. I relented after making sure I tell her what is entailed in that particular choice.
I had planned on making Fajr the last prayer for her but it seemed that she has her own mind. So be it.

Last October, N turned 7, though I still think of her as being five due to her character and height. Even F forgets that she is now seven and confidently answered,

"Five," when the lifeguard at the pool asked him how old N was.

At the moment, even I didn't interject immediately at his given response, and only after a few lingering minutes did it occur to me that N is not five, but seven. I said,

"N's not five. She's seven," to F, who simply looked blankly at me and then said,

"Oh."

Fancy that. Two parents who can't even remember how old their middle daughter is.

N is now doing Asr. So when I have my period, S and N will both do their prayers without me.

Just recently, I had told them to perform their Asr together. They went upstairs before me. After a while, I went upstairs to check on them, and S was already in the process of bowing and prostrating, while N was still putting on her prayer garment. It was to my horror that I saw S leaving her sister by praying first, because I know that N doesn't really know how to pray by herself yet. So I said to her,

"Oh no, N, do you know how to pray by yourself?"

Her face showed no perturbance, which is normal for her, and she simply said,

"No. But S is just doing her extra prayer,"

to which I immediately and confidently replied,

"No. She's not doing her extra prayer. She's already praying Asr. She doesn't know how to do extra prayer."

S was just finishing her last rakaah then and after giving the salams, she said to me,
"I was doing my extra prayer. I told N I was going to do my extra prayer."

I was too surprised to think straight and with a stupid expression on my face, asked,

"Why?"

"So she wouldn't worry," said S, as if I, as the mother, should have known that all along.

"Oh," was all I said, mouth still agape.

"You know how to do the extra prayer?" I asked her.

"How many standings did you do?" I asked her again.

"Two," she said.

"Oh...uh. Good," I said and left them to pray Asr together.

I left my two girls, feeling ultimate surprise and disbelief. It wasn't until much later that I praised S for doing the extra prayer, as I still didn't get over the disbelief in finding out that my eight year old is doing her extra prayer with not the slightest encouragement from the parents.