וְעַתָּ֥ה בְנִ֖י שְׁמַ֣ע בְּקֹלִ֑י וְק֧וּם בְּרַח־לְךָ֛ אֶל־לָבָ֥ן אָחִ֖י חָרָֽנָה׃
און אַצונד, מײַן זון, הער צו מײַן קָול, און שטײ אױף, אַנטלױף דיר צו מײַן ברודער לָבָנען קײן חָרָן.
Or HaChaim
ועתה בני, "and now my son, etc." This has to be understood in the same vein as the statement by our sages that one should be a penitent a day before one's death (Avot 2,10). Rebeccah reminded Jacob that no one is assured of his life for even a single day. As a result one must always be penitent. This is why she chose the expression "now." קום ברח, "arise and flee!" She urged Jacob to flee at once although Esau had indicated he would not murder Jacob until after his father's death. Rebeccah was afraid that Isaac might die at any time, thus enabling Esau to try and carry out his evil intention.
Radak
ועתה..חרנה, she had heard that her brother had migrated from Ur Casdim to Charan.