I can't stop her from thumbsucking

My LO is 4.5 months and loooves to suck her thumb. She has a pacifier and will use it, but if the paci is even slightly inconvenient, she goes for the thumb. At night and naps, she will suck her paci for a minute or two, but then she spits it out and furiously sucks on her thumb. I love the self soothing aspect, but I am very concerned about her oral-motor and palate/tooth development. For context, my partner's cousin was a thumbsucker and had to have surgery on his palate, in addition to braces. Is this something I can stop? I try to put her paci in whenever I see her go for the thumb when she is up, but I don't know what else to do. Anyone else battle with your little one's thumbs? via /r/Parenting https://ift.tt/2VMOv5B