Mum cat has been gone over 2hours now!

[Green199]

Hi. So my 1 year old cat gave birth to a litter of 6 3 days ago! (not easy for her, I know) all the babies are strong, feeding well and have plump bellies.
Mum cat has been great, looking after them sooo well.
However I have let her out and she's usually good and goes out and sniffs about and comes back, she's not too adventurous unless in heat...
So I let her out about 10pm and she just hasn't come back... The babies were fed about 9... They have had a wiggle and little moan but no major squealing yet... Should I be concerned about the babies getting hungry? They are warm enough. I'm just worried mum has either done a runner as she's so overwhelmed and needs a break or she's come back into heat!! There's no explanation for her going for over 2hours... Stressing out for the babies as its midnight and I can't feed them and she may not get in if I fall asleep...
Any advice on how long 3day old kittens can realistically go without mum's milk? They still have full, plump bellies from what I can see but not sure if that makes a difference?
Thank you. J

Why on earth has she not been spayed already?
She very young to be having kittens, poor thing.
Hope she comes back soon and you keep her in from now on

Did she come back OP? As dementedpixie said, why are you letting her out of she hasn't been spayed? You will almost certainly get another litter of kittens now. Poor cat.

Yes i do think you should get her spayed. I recently had mine done before I let her out.

Has she come back? I can't imagine she'd leave the kittens for too long

Is she back yet?
I think you should go to pets at home for advice on hand feeding them, or hand them over to a rescue if she doesn't come back soon. They are newborns so will probably need to feed often.
I really hope she comes back though!

Why you letting her out when she's not being spayed?! How irresponsible can someone get!

@Green199
Did mum-cat return?