Making this sweet vest a bit bigger (the biggest size is 3yo) for my oldest son. Am aiming for a size 4yo.

Have added 24 sts to the cast on.

I made the body of the vest about 5 cm longer than the biggest size. I also increased the depth of the armholes and the neck slit. I used 5 buttons for the closing (instead of 3) as the slit is quite a bit deeper. I used every last inch of the one skein of Alpaca 1 I had, so that was a bit too exciting near the end.
I.e. if you want to make a bigger size (more than one size bigger) get more of the alpaca!

This ended up really perfect and fits my 4yo (size 116) perfectly now. Hopefully it will last the whole season.