Sizing question

I bought this pattern recently during the recent discount offering! Yay! I am pretty excited and scared to sew this. I am planning to make view B first. My two year old is really petite. She measures - 19 inches chest, 18.5 waist, dress length - 18 would be around her knees. As per measurements I should make a 12-18 month size. I read that the pattern is snug at the top, my kiddo has a huge head! Should I size up to 18-24 months?