For the past month or so M (9 months) has been sucking her thumb when she's going to sleep. I was ok with this and it seemed like a good soothing mechanism / sleep cue. Now in the last few days she's been sucking it a lot more. Today we were at the grocery store and she was wide awake and happy looking around and wanted to suck her thumb the whole time! DH has been trying to discourage it but I'm not sure if we should be pulling it away or just go with it. She stopped using the newborn paci when she was 3 or 4 months and we never introduced another one. Do you think a pacifier is better than a thumb because you can take it away?