Abbey never took to one. She just didn't seem to need it.
Meg had a teddy bear. Kayla had a blanket. I kept identical extras just in case. I think they got attached around nine months and gave them up at about 6 give or take.
Ellie is still thouroughly attached to her "lamby" She had one before she came home with us and has completely loved the fuzz right off of it. The nose is falling off and there's a hole in one of the feet where the stuffing is falling out.

It stays on a shelf next to her bed and isn't allowed to go anywhere.
I have since gotten 3 "lamby's" that are identical to the original. One is for home use, one stays in her backpack for school, church, therapy, the car, etc. and the third is an extra just in case.
She isn't showing any signs that she'll be ready to give up her lamby's any time soon. I'm okay with that but I do worry a little about teasing. It hasn't started yet but I'm sure it will and kids have enough to tease her about.