At what age is it acceptable to allow a child to keep their “lovey” (small blanket or stuffed animal) with them in the crib?

At what age is it acceptable to allow a child to keep their “lovey” (small blanket or stuffed animal) with them in the crib?

Babies should not have pillows, stuffed animals etc in the bassinet, crib or bed with them until they are 1 and a half years old. They won’t miss these things in bed if they haven’t been exposed to them yet and they are much safer sleeping without them.