A Four Month Old Decided to Suck Her Thumb

Charlotte, out of the blue, decided to suck her thumb during memorial day weekend. I'm wondering if there is something to the four month mark. Anna took a pacifier until almost the day she turned four months old and then spit it out, never to take it again. She tried her thumb once, I've got pictures to prove it, and then decided on the first and second fingers on her left hand. Abby never sucked on anything. She never wanted anything in her mouth. It was perhaps the hardest thing I've ever had to do when we tried to get her to eat solids.

So, here we have Charlotte, our little thumbsucker. Hopefully, not something that continues for ages, but it is her own way to self-sooth. :)