I have a 3+ year old and am currently 31 weeks pregnant (due in July). I weaned my older son in November (at age 2.75) when the pregnancy made it just too painful to continue. My son really, really loved nursing, and I was surprised that he let go of it as easily as he did. He still holds "the nurses" when he needs comfort, and sometimes at bedtime, and that's fine.
As we get closer to the baby's arrival, my son has started talking about how he wants to start nursing again. Last night he told me that he wanted to "suck all the yummy milk out." I am a bit surprised by this, since it has been almost 6 months since he has actually nursed. Clearly the breast was very meaningful to him.
Various issues: I don't have any milk for him to drink and I am not interested in tandem nursing. We have talked a bit about how the milk (which isn't there now) will be for the baby, since the baby can't eat anything else. My son's response is to pretend to be a baby, with the theory that babies get milk and therefore he does too.
I'd love to hear how others have dealt with this. I don't want to take the breast away from him (even if he's not nursing from it) but I'd also like him to understand that he isn't going to start nursing once the baby gets here and I start lactating again.
I think though they talk about it they really don't initiate it at all. I am not sure how to help him with it. I am sure it will be hard when he still wants to nurse but only the baby will get too. Maybe get him a special nursing toy or two that he only gets while the baby is nursing. To help take his mind off of it.
He's really pushing it - putting his mouth on my breast, not quite sucking but going through the motions. I have told him firmly no, and that if he continues we will put it away, but the temptation is there. I'm not sure how to cut this off. Hot pepper on the nipple?
If you really don't want to nurse your son anymore, you have to get to the root of the issue - jealousy. He is used to being an only child, he has you to himself. Yet already the new baby is taking up some of his time with you just by the fact that you are talking about it and preparing. A new baby changes the dynamics of the family, and he needs to know where he fits in. Children often regress in behaviors when they are stressed.
Make sure he feels that you love him just as much even though he isn't nursing. Spend as much one-on-one time with him as you can without involving the baby. Distraction and redirection work well for keeping toddler's minds off of nursing. Keep him busy with things he likes to do more than he likes nursing. For instance, take him to the park, library storytimes, a playgroup for his age level, swimming, the zoo, a children's museum. Remind him of all the fun things he can do that the new baby can't do.
Try to make him feel special, not left out. I know this may not seem directly related to breastfeeding, but he probably only wants to nurse to feel close to you. He needs to gain that security in other ways.