No, that's completely impossible. First of all, when her brother, Sora, died, he turned into the Hollow "Acidwire", who doesn't resemble Ulquiorra in the slightest. Secondly, Sora was purified by Ichigo's Zanpakuto, which means he is currently residing in Soul Society as a regular Soul. And even if Sora wasn't purified, he was far too young to have already become a Menos, Ulquiorra doesn't look or even act like him at all and we've had a glimpse of Ulquiorra's past life as a Hollow and again, he didn't resemble Acidwire in the slightest.