Valmiki Ramayana Ayodhya Kanda Sarga 53 Shloka 19

सौमित्रे Lakshmana, मम जनन्या by my mother, कस्मिन् जात्यन्तरे in some previous birth, स्त्रियः women, पुत्रैः with sons, वियोजिताः separated, तस्मात् for that reason, एतत् all this, उपस्थितम् befallen, नूनम् certainly.

O Lakshmana, surely in one of her previous births did my mother separate women from their sons. That is why this (calamity) has befallen her.