16 week sonogram and a 16 month old

This morning, Russell, Jackson and I went to my sonogram. We have a very healthy and active Baby on the way. The doctor said he enjoyed watching our active baby. Our little one was moving around so much I asked if it was normal. The doc reassured me that all the movement was a good thing. The doctor said they can often tell the gender at this point (16 weeks tomorrow) but they couldn't with our little guy/girl. They waffled back and forth and said it was just too close to call. We go back in about a month for another sonogram so we should know then. Jackson also has a big day because he is officially 1 1/3 years old! Are we going to be able to keep up with all these birthdays once Baby #2 arrives?!?!