She looks too much like her mother to determine based on characteristics, but the mother's erratic behavior after her separation indicates she was already carrying at the time. Young mothers are predisposed to madness.

[After a pause, she adds, like spectating some incomprehensible object in an art gallery - ]

Given that this is a fiction where such a thing would matter, it's also obvious they would still be in love had they remained together. Heh.