My baby wore the smallest size home from the hospital, but it was quite big on her (she weighed 8 lbs when leaving the hospital). It fit her the whole first summer, until she weighed about 13 lbs. Perfect for a christening, naming, or any special party. I made the largest size for her 1 YR Birthday, which should fit her until about 16 months.
This pattern has an intense lace going throughout. When keeping pattern correct after shaping, remember to yarn over and decrease evenly. That is, if you can’t complete a yarn over because it’s at the very beginning or end of a row, leave out the corresponding K2tog or SSK, or reduce an S2KP to a regular decrease. If the ‘footwork is too difficult, try leaving out the YO closest to the shaped edge.