Thank you! I hoped that it might be as simple as increasing the needle size and maybe using two strands of yarn.
The blanket actually indicated size 10.5 needles and two strands of yarn, so the pattern for the blanket is much bigger. I'm happy to increase the needle size and double the yarn for the sweater, if it seems like that would work.
I'll include a picture of the sweater and blanket. The pattern breaks the sweater down into separate sections, so I'm guessing that it's not a top-down style. Remember, this is my first sweater
Thanks again for your help and the quick responses!