So, here we are in Week 18, and your Mom is still pretty tiny! Considering you're the size of a sweet potato, one would think that she would be a bit bigger; but she has a naturally small frame, so we're not expecting her to get too huge.
But, it seems like ever since our appointment yesterday, your Mom has been on an eating tear. Check out her menu from yesterday:
Breakfast: Count Chocula
Lunch #1 (around 10:30): Lean Cuisine Pepperoni Pizza
apple sauce
orange

Lunch #2 (around 1:00): Wendy's Chicken nuggets and fries
Lunch #3 (around 4): Peanut Butter and Jelly
Dinner (at 7): Lasagna Bake
Dessert (at 8): Moolenium Crunch Ice Cream
Latenight Snack (at 10): Frosted Mini Wheats
She had more lunches than a Hobbit! Now, I pride myself on eating A LOT, but I couldn't keep up with her yesterday! So, I wouldn't be surprised if we saw some major belly growth in the next coming weeks!
But, from what I can tell, it doesn't seem that you two are starving for nutrients. According to the Bump, the average weight for an 18 week old fetus is 6.7 ounces...and as of Monday, they calculated that you weigh 9 ounces!
So both Mommy and Baby Boy have been chowing down! Nom nom nom!