My daughter was an only child, but she was incredibly intelligent.
I had her in daycare to keep her stimulated.
Don't get me wrong, I was very hands-on and taught her many things myself, but I also had to work.
She went to Head Start and was advanced enough that she actually began kindergarten at 4.
In my opinion, you can't hold children back because they are your "only" child. I know it's hard to let them go, but if THEY are ready, that's what matters.
I know some mothers feel that their kids should be at home with mom as much as possible. I was a single, working mom and I needed my daughter to learn that there were lots of things outside our world.
She flourished in Head Start, her teachers told me she was ready for kindergarten and they really couldn't do any more for her.
Was it about me not being ready to let her go or was it about doing what was best for her?
She went to kindergarten and did just fine.
I understand that your daughter is your only child, but in my opinion, it might be good for her to socialize with other kids. I have known plenty of only children who didn't do well in kindergarten because they hadn't been exposed to sharing, taking turns, intermingling.
It sounds like you are thinking of having her in preschool 6 hours a week.
That's not excessive, by any means. I think she might likely benefit from it.
I, personally, don't think you should be reluctant because she is your only child. Daycare and preschool can give her a chance to understand that she's the only child in your family, but not the only child in the world.
Let her make friends and have experiences outside the family unit.
I think it would be good for her.
Again, just my opinion.