Maybe her body is just expelling more of the afterbirth inside of her? I know for about a year after having a child you can still expell things from your body after childbirth. Of course most women get rid of the majority after about a month or so.
But on a more serious note their is a possibility she is expelling afterbirth or tings related to this, but is also could have an infection or hemmorahage? Im not suggesting this, but i do believe she should go to her doctor on tuesday and double check for these things. With a C-section many more complications can arise with infection.
But im pretty sure she is just expelling material from childbirth from her body.
Of course im not a professional, im a mother of three and just thought id lend you my thougts. Either way examination is recommended.
good luck.. let us know what her diagnosis is, im truly curious.