is this normal?

Hello there,

My cat Misha is 40 days pregnant today. Everything is going very good. She
seems happy, she "talks" and purrs as much as she always did. She's been
more quiet in the sence that she doesn't play so much or climb the cat tree
so much anymore but I would imagine that is normal. I called her vet
yesterday morning to make sure I was doing everything all right. It is a
long time ago we had pregnancy in the house, as my 3 other cats are spayed.

The vet adviced me to start mixing kitten food with her usual food... and
increase the kitten food as time goes. This is very good for pregnant and
nursing cats.
Here comes the thing...
Misha has been eating SO much lately. I had noticed that she was eating more
before I put her on kitten food, which is normal with the pregnancy... But
now that I feed her away from the other ones, I notice it even more. She is
asking for food very often. I'm wondering if it's ok? Should I give her food
each time she asks for it? or is this just because she likes it so much?
She,s always been a good eater, but now I'm afraid to give her too much. I
was thinking I could give her the kitten food 3 times a day, and if she is
more hungry, the "adult" food is always available at "the normal cat food
place". What should I do? I know she needs to eat smaller portions, more
often in the day, because of the pregnancy and the belly taking so much
space ...
Other than that, she rests a lot... and as I said, everything is fine, her
litter box activities are normal as well... Oh and talking about box... she
even already took property of the birthing box I put out for her in a quiet
corner of my room.

Thanks for help and advice... As you can see, I'm watching her pregnancy
closely... counting the days and making sure all is normal. I know I'll get
messages telling me that this cat shoudl be spayed and I'm such an idiot to
let her have babies... tell if you like.

Regards,
Mia and Misha.