When I first looked at the picture I thought it was a blouse she was wearing under the vest - I clicked on the picture and got a full size image - it has a really neat pattern - bobbles are criss-crossed all over and in the middle of the criss-crosses are a 4 leaf pattern. Now I can't tell if the bobbles are knitted or crocheted on after the sweater was completed. The sleeve also has a small section that is crocheted. I wish I could see the front of the sweater. The more that I look at it, it almost looks like it was knitted in stockinette stitch and then the flowers and circles were crocheted on afterwards.
I haven't seen any pattern but maybe with looking at the picture some and knitting up a gauage swatch you could design one.
It is a really neat sweater... looks fun to wear.
__________________
OTN - lacy sweater and just beginning another pair of socks - toe up
FO's: garterstitch scarf, dropped stitch cable fingerless mittens, socks for Christmas, and 6 baby hats, cabled toddler hat, hat for mom, MIL socks