Gauge swatches:

T5
7.5”/27 sts= 3.6 stitches per inch
13 rows/2 inches= 6.5 rows per inch

T7
8”/27sts= 3.4 stitches per inch
12 rows/2”= 5 rows per inch

Pattern gauge
20 sts/4”= 5 sts per inch
26 rows/4”= 6 rows per inch

96 stitch circumference =
96=20
X=13.6
65

Knitted top down instead of bottom up. started with a thinner yarn to make the cast on easier on the machine.

Cast on 65 stitches with a different thinner yellow yarn.
Knit 12 rows in rib in tension 5.
Change yarn and knit bubble yarn, T7 for 120 rows
Gathered the stitches instead of doing decreases at the bottom.

HAT: 6 rows rib with thinner yarn in T2
3” (15 rows) of bubble yarn in T7
With thinner yarn:
12 rows crown increasingly tightening the tension. Gathered stitches instead of decreasing of crown.

The sack seems very long but the dimensions are as stated by pattern, so I guess babies just have long legs… Ha ha ha