Just adopted, not peeing

We picked up our kittens yesterday at 5:30 pm and they ate at 4:00 (used litter) and 8:00 am, and slept through the night (from 9:30 to 7:00--would have been longer, if my daughter hadn't woken them up).

One of them obviously needs to go pee/poo as she will eat, stop to scratch the ground, then continue eating, then stop to scratch...

If I leave the room, one of them starts mewing.

We have a litter box filled with pine pellets, clean, but they are not peeing at all.

Should we be worried?  Is there anything I can do to help them pee for the first time?

It is now 9 am.

You can surely stimulate them, as if they were infants. Thereby also showing you are their Mom. After they do pee, soak a little pee in toalett-paper, and lay in the litter, so it get the smell of their own pee.

It is quite common they dont pee the first day in the new home, so you dont need to worry yet.

But if you want to help things on the way, this is prob the trick.

Good luck!

Thanks for the advice... I tried stimulating them with a wet cotton pad, and... nothing, but they were pretty annoyed at me, and I didn't realize they could tuck their tails in like that!

They finally peed, 23 hours after their last pee.  That's gotta hurt!

So all of us are, quite literally, relieved.  All is fine in the universe.

Cats are such amazing creatures, so clean.  Shortly after, the first poop followed.