Mommies...Did anyone else feel sad when...?

I feel ya my son is 19 months and I cried like a baby the night before his first birthday I looked through his baby book and even now I go through pics from the day he was born and all the pics we had taken we did 3 6 9 12 and 18 months and its crazy how much he still looks the same from when he was born but looks older and hes so independent he did everything really early but now hes starting to talk alot and im having another baby the end of may (a girl) and he hold up my shirt gives my belly kisses rubs my belly says hi baby he also likes to poke my belly button and says owe he thinks its funny hes never been around another baby but I hope hes a great big brother I asked him the other night if he was going to be my little boy forever and he said nooooo shaking his head it made me sad :(