I strongly suggest getting plenty of support and encouragement through La Leche League (llli.org or a local group). I tandem nursed through 3 pregnancies. Only 1 of the 3 older children weaned himself during the pregnancy, although I've read that the majority of toddlers will wean themselves during their mother's pregnancy, whether due to a change in the taste, texture, or volume of milk their mother produces. If your toddler has reflux and allergies, it is probably important to continue to nurse him. Colostrum won't hurt him, if in fact that's what it is. Like your son, my daughters were very slow to rely on solid food, and it gave me peace to know that they were still receiving excellent nutrition by continuing to breastfeed. If your Braxton Hicks contractions aren't too frequent or intense and there aren't other signs of premature labor, you're probably fine to continue nursing. You should check with your care provider just in case, but be aware that s/he probably has little to no experience or education regarding tandem nursing, although that is the norm in many other cultures (hence my suggestion to get info from LLL). Best of luck, and congratulations on your resolve to do what's best for both of your children!