Nursing mom

I have a stray cat I take care of that ran inside my house into a box that i leave out for my inside babies and she had her kittens yesterday well today i noticed when she went to the bathroom she had blood in her stool is this normal for a mama cat to do the day after she's just had kittens?

It is quite normal for a cat to have some bleeding from the vagina for a couple of days after giving birth. Are you sure the bleeding was in the stool? I would keep a close watch and if you are sure she has blood in the stool then a vet visit is in order.