[hg808]

Similar situation here, except that DS is older, but is smaller for his age (about 50% percentile) and DD is taller (at 100% for her age). DS used to be more agressive at first, but now DD gives him a run for his money. I would say that now they kiss about 1/2 of the time and fight 1/2 the time, but are truly inseparable. (We brought DD home 5 months ago).

What helped us was that we started to tell DS, "Now you are a BIG BOY, and M. is just a LITTLE BABY, so you need to be very gentle with her and protect her". Ironically, now they both think of the other one as a "little baby", so when I ask, "where's the baby?", they point at each other (DS is 3 years 3 months old, DD is 19 months old).

I really liked the book "Sibling Rivalry", but found it being geared towards older kids. The takeaway for me was that you should enforce and explain a different role for each child in the family.