Re: Any advice on explaining b****** to my 3yr old?
How about some books about babies breastfeeding? We had a few that we read together and I think they helped my DD a bit (my DD was still nursing when baby was born, though, so YMMV).
We Like to Nurse
We Like to Nurse Too
What Baby Needs
I second the basket of special toys/books/snacks that just comes out when baby needs to nurse. It makes it a special time for everybody.
Catherine, tandem nursing mama to Preschooler Girl 9/08 and Toddler Boy 3/11
Breastfeeding for 4 years and counting!