How to stop a thumb sucker

I was just wondering if anyone has any suggestions on how to stop a habital thumb sucker. My 5 1/2 yr old son and my almost 4 yr old son still suck their thumbs. They do it all the time. Not just when the are scared of tired either. I have tried hot sauce, spanking, and even rewarding them when the don't suck their thumbs and nothing seems to work. If any one could give me any advice at all, I would greatly appreciate it. I feel like I am at my witts end,

Thanks,
Brandy Bodiford

[treazzure007]

my son began sucking his thumb at 2 1/2 years of age b/c he was at first mimicking a girl in his daycare, but it became a habit right after that!  i found this product called MAVALA STOP that worked within 1 week.  i even used it to stop biting my nails.  designed for nail biters and finger suckers, it goes on like clear nail polish but tastes terribly bitter, awful.  stays on too and not easy to get rid of.  to break the habit, the child just has to have access cut off for a while

[margypops]

I wouldnt spank a child for a habit he cant help! the 4 year old is copying the 5 year old for a start so when the 5 year old stops the younger one probably will.You could try ignoring it,if they are getting attention about it that is enough Negative attention is better than none.Have you or your husband done it has anyone else in the Family bitten their nails in front of the kids,  How about doing more with them ask Dad to do Guy stuff Ball games, reading keep them busy boredom can cause all kinds of Habits. I do believe their is stuff out there but not certain what.