So, I couldn't do it. Finish the sweater before starting on the baby blanket. Big brother's sweater was transferred to a set of 3mm needles (which very seldom are in use as they are awful) and put on hold, and mommy happily cast on for the baby blanket on the 2,5mm needles.
Have just started on the colorwork, and am increasingly worried that the combination of colors will turn out too dark. I was hoping for the pink and the purple to be a bit brighter, and I feel that the grey is very brownish.
Well, I will have to knit a bit more to really see how it will turn out.