My 2.5 year old was night weaned at about 14 months. He had never used a pacifier or sucked his thumb, and night weaning did not prompt either. Recently, about a year after night weaning (but still nursing during the day) he did try to experiment with thumb sucking during "quiet times" like reading stories or watching a video. I think he overheard my husband make some comment like, "Oh great, now he's sucking his thumb" and never did it again. As a thumb sucker till the age of 9 myself, I am not that off-put or worried about a potential thumb-sucking habit. My ds does chew on a corner of his blanket whenever the blanket is near. He also bites his nails and still chews on all plastc and plush toys though he is no longer teething. So much for EBF "curing" the oral urge!!